linux/net/sched/cls_api.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/sched/cls_api.c Packet classifier API.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* Changes:
*
* Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/kmod.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 09:04:11 +01:00
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/rhashtable.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <net/tc_act/tc_pedit.h>
#include <net/tc_act/tc_mirred.h>
#include <net/tc_act/tc_vlan.h>
#include <net/tc_act/tc_tunnel_key.h>
#include <net/tc_act/tc_csum.h>
#include <net/tc_act/tc_gact.h>
#include <net/tc_act/tc_police.h>
#include <net/tc_act/tc_sample.h>
#include <net/tc_act/tc_skbedit.h>
net/sched: Introduce action ct Allow sending a packet to conntrack module for connection tracking. The packet will be marked with conntrack connection's state, and any metadata such as conntrack mark and label. This state metadata can later be matched against with tc classifers, for example with the flower classifier as below. In addition to committing new connections the user can optionally specific a zone to track within, set a mark/label and configure nat with an address range and port range. Usage is as follows: $ tc qdisc add dev ens1f0_0 ingress $ tc qdisc add dev ens1f0_1 ingress $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 0 proto ip \ flower ip_proto tcp ct_state -trk \ action ct zone 2 pipe \ action goto chain 2 $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 2 proto ip \ flower ct_state +trk+new \ action ct zone 2 commit mark 0xbb nat src addr 5.5.5.7 pipe \ action mirred egress redirect dev ens1f0_1 $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 2 proto ip \ flower ct_zone 2 ct_mark 0xbb ct_state +trk+est \ action ct nat pipe \ action mirred egress redirect dev ens1f0_1 $ tc filter add dev ens1f0_1 ingress \ prio 1 chain 0 proto ip \ flower ip_proto tcp ct_state -trk \ action ct zone 2 pipe \ action goto chain 1 $ tc filter add dev ens1f0_1 ingress \ prio 1 chain 1 proto ip \ flower ct_zone 2 ct_mark 0xbb ct_state +trk+est \ action ct nat pipe \ action mirred egress redirect dev ens1f0_0 Signed-off-by: Paul Blakey <paulb@mellanox.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Yossi Kuperman <yossiku@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Changelog: V5->V6: Added CONFIG_NF_DEFRAG_IPV6 in handle fragments ipv6 case V4->V5: Reordered nf_conntrack_put() in tcf_ct_skb_nfct_cached() V3->V4: Added strict_start_type for act_ct policy V2->V3: Fixed david's comments: Removed extra newline after rcu in tcf_ct_params , and indent of break in act_ct.c V1->V2: Fixed parsing of ranges TCA_CT_NAT_IPV6_MAX as 'else' case overwritten ipv4 max Refactored NAT_PORT_MIN_MAX range handling as well Added ipv4/ipv6 defragmentation Removed extra skb pull push of nw offset in exectute nat Refactored tcf_ct_skb_network_trim after pull Removed TCA_ACT_CT define Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 09:30:48 +02:00
#include <net/tc_act/tc_ct.h>
extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
/* The list of all installed classifier types */
static LIST_HEAD(tcf_proto_base);
/* Protects list of registered TC modules. It is pure SMP lock. */
static DEFINE_RWLOCK(cls_mod_lock);
/* Find classifier type by string name */
static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
{
const struct tcf_proto_ops *t, *res = NULL;
if (kind) {
read_lock(&cls_mod_lock);
list_for_each_entry(t, &tcf_proto_base, head) {
if (strcmp(kind, t->kind) == 0) {
if (try_module_get(t->owner))
res = t;
break;
}
}
read_unlock(&cls_mod_lock);
}
return res;
}
static const struct tcf_proto_ops *
tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
struct netlink_ext_ack *extack)
{
const struct tcf_proto_ops *ops;
ops = __tcf_proto_lookup_ops(kind);
if (ops)
return ops;
#ifdef CONFIG_MODULES
if (rtnl_held)
rtnl_unlock();
request_module("cls_%s", kind);
if (rtnl_held)
rtnl_lock();
ops = __tcf_proto_lookup_ops(kind);
/* We dropped the RTNL semaphore in order to perform
* the module load. So, even if we succeeded in loading
* the module we have to replay the request. We indicate
* this using -EAGAIN.
*/
if (ops) {
module_put(ops->owner);
return ERR_PTR(-EAGAIN);
}
#endif
NL_SET_ERR_MSG(extack, "TC classifier not found");
return ERR_PTR(-ENOENT);
}
/* Register(unregister) new classifier type */
int register_tcf_proto_ops(struct tcf_proto_ops *ops)
{
struct tcf_proto_ops *t;
int rc = -EEXIST;
write_lock(&cls_mod_lock);
list_for_each_entry(t, &tcf_proto_base, head)
if (!strcmp(ops->kind, t->kind))
goto out;
list_add_tail(&ops->head, &tcf_proto_base);
rc = 0;
out:
write_unlock(&cls_mod_lock);
return rc;
}
EXPORT_SYMBOL(register_tcf_proto_ops);
static struct workqueue_struct *tc_filter_wq;
int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
{
struct tcf_proto_ops *t;
int rc = -ENOENT;
net: sched: fix call_rcu() race on classifier module unloads Vijay reported that a loop as simple as ... while true; do tc qdisc add dev foo root handle 1: prio tc filter add dev foo parent 1: u32 match u32 0 0 flowid 1 tc qdisc del dev foo root rmmod cls_u32 done ... will panic the kernel. Moreover, he bisected the change apparently introducing it to 78fd1d0ab072 ("netlink: Re-add locking to netlink_lookup() and seq walker"). The removal of synchronize_net() from the netlink socket triggering the qdisc to be removed, seems to have uncovered an RCU resp. module reference count race from the tc API. Given that RCU conversion was done after e341694e3eb5 ("netlink: Convert netlink_lookup() to use RCU protected hash table") which added the synchronize_net() originally, occasion of hitting the bug was less likely (not impossible though): When qdiscs that i) support attaching classifiers and, ii) have at least one of them attached, get deleted, they invoke tcf_destroy_chain(), and thus call into ->destroy() handler from a classifier module. After RCU conversion, all classifier that have an internal prio list, unlink them and initiate freeing via call_rcu() deferral. Meanhile, tcf_destroy() releases already reference to the tp->ops->owner module before the queued RCU callback handler has been invoked. Subsequent rmmod on the classifier module is then not prevented since all module references are already dropped. By the time, the kernel invokes the RCU callback handler from the module, that function address is then invalid. One way to fix it would be to add an rcu_barrier() to unregister_tcf_proto_ops() to wait for all pending call_rcu()s to complete. synchronize_rcu() is not appropriate as under heavy RCU callback load, registered call_rcu()s could be deferred longer than a grace period. In case we don't have any pending call_rcu()s, the barrier is allowed to return immediately. Since we came here via unregister_tcf_proto_ops(), there are no users of a given classifier anymore. Further nested call_rcu()s pointing into the module space are not being done anywhere. Only cls_bpf_delete_prog() may schedule a work item, to unlock pages eventually, but that is not in the range/context of cls_bpf anymore. Fixes: 25d8c0d55f24 ("net: rcu-ify tcf_proto") Fixes: 9888faefe132 ("net: sched: cls_basic use RCU") Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Thomas Graf <tgraf@suug.ch> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-20 17:13:33 +02:00
/* Wait for outstanding call_rcu()s, if any, from a
* tcf_proto_ops's destroy() handler.
*/
rcu_barrier();
flush_workqueue(tc_filter_wq);
net: sched: fix call_rcu() race on classifier module unloads Vijay reported that a loop as simple as ... while true; do tc qdisc add dev foo root handle 1: prio tc filter add dev foo parent 1: u32 match u32 0 0 flowid 1 tc qdisc del dev foo root rmmod cls_u32 done ... will panic the kernel. Moreover, he bisected the change apparently introducing it to 78fd1d0ab072 ("netlink: Re-add locking to netlink_lookup() and seq walker"). The removal of synchronize_net() from the netlink socket triggering the qdisc to be removed, seems to have uncovered an RCU resp. module reference count race from the tc API. Given that RCU conversion was done after e341694e3eb5 ("netlink: Convert netlink_lookup() to use RCU protected hash table") which added the synchronize_net() originally, occasion of hitting the bug was less likely (not impossible though): When qdiscs that i) support attaching classifiers and, ii) have at least one of them attached, get deleted, they invoke tcf_destroy_chain(), and thus call into ->destroy() handler from a classifier module. After RCU conversion, all classifier that have an internal prio list, unlink them and initiate freeing via call_rcu() deferral. Meanhile, tcf_destroy() releases already reference to the tp->ops->owner module before the queued RCU callback handler has been invoked. Subsequent rmmod on the classifier module is then not prevented since all module references are already dropped. By the time, the kernel invokes the RCU callback handler from the module, that function address is then invalid. One way to fix it would be to add an rcu_barrier() to unregister_tcf_proto_ops() to wait for all pending call_rcu()s to complete. synchronize_rcu() is not appropriate as under heavy RCU callback load, registered call_rcu()s could be deferred longer than a grace period. In case we don't have any pending call_rcu()s, the barrier is allowed to return immediately. Since we came here via unregister_tcf_proto_ops(), there are no users of a given classifier anymore. Further nested call_rcu()s pointing into the module space are not being done anywhere. Only cls_bpf_delete_prog() may schedule a work item, to unlock pages eventually, but that is not in the range/context of cls_bpf anymore. Fixes: 25d8c0d55f24 ("net: rcu-ify tcf_proto") Fixes: 9888faefe132 ("net: sched: cls_basic use RCU") Reported-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Thomas Graf <tgraf@suug.ch> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-20 17:13:33 +02:00
write_lock(&cls_mod_lock);
list_for_each_entry(t, &tcf_proto_base, head) {
if (t == ops) {
list_del(&t->head);
rc = 0;
break;
}
}
write_unlock(&cls_mod_lock);
return rc;
}
EXPORT_SYMBOL(unregister_tcf_proto_ops);
bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
{
INIT_RCU_WORK(rwork, func);
return queue_rcu_work(tc_filter_wq, rwork);
}
EXPORT_SYMBOL(tcf_queue_work);
/* Select new prio value from the range, managed by kernel. */
static inline u32 tcf_auto_prio(struct tcf_proto *tp)
{
u32 first = TC_H_MAKE(0xC0000000U, 0U);
if (tp)
first = tp->prio - 1;
return TC_H_MAJ(first);
}
static bool tcf_proto_is_unlocked(const char *kind)
{
const struct tcf_proto_ops *ops;
bool ret;
ops = tcf_proto_lookup_ops(kind, false, NULL);
/* On error return false to take rtnl lock. Proto lookup/create
* functions will perform lookup again and properly handle errors.
*/
if (IS_ERR(ops))
return false;
ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
module_put(ops->owner);
return ret;
}
static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
u32 prio, struct tcf_chain *chain,
bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct tcf_proto *tp;
int err;
tp = kzalloc(sizeof(*tp), GFP_KERNEL);
if (!tp)
return ERR_PTR(-ENOBUFS);
tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
if (IS_ERR(tp->ops)) {
err = PTR_ERR(tp->ops);
goto errout;
}
tp->classify = tp->ops->classify;
tp->protocol = protocol;
tp->prio = prio;
tp->chain = chain;
spin_lock_init(&tp->lock);
refcount_set(&tp->refcnt, 1);
err = tp->ops->init(tp);
if (err) {
module_put(tp->ops->owner);
goto errout;
}
return tp;
errout:
kfree(tp);
return ERR_PTR(err);
}
static void tcf_proto_get(struct tcf_proto *tp)
{
refcount_inc(&tp->refcnt);
}
static void tcf_chain_put(struct tcf_chain *chain);
static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
struct netlink_ext_ack *extack)
{
tp->ops->destroy(tp, rtnl_held, extack);
tcf_chain_put(tp->chain);
module_put(tp->ops->owner);
kfree_rcu(tp, rcu);
}
static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
struct netlink_ext_ack *extack)
{
if (refcount_dec_and_test(&tp->refcnt))
tcf_proto_destroy(tp, rtnl_held, extack);
}
static int walker_check_empty(struct tcf_proto *tp, void *fh,
struct tcf_walker *arg)
{
if (fh) {
arg->nonempty = true;
return -1;
}
return 0;
}
static bool tcf_proto_is_empty(struct tcf_proto *tp, bool rtnl_held)
{
struct tcf_walker walker = { .fn = walker_check_empty, };
if (tp->ops->walk) {
tp->ops->walk(tp, &walker, rtnl_held);
return !walker.nonempty;
}
return true;
}
static bool tcf_proto_check_delete(struct tcf_proto *tp, bool rtnl_held)
{
spin_lock(&tp->lock);
if (tcf_proto_is_empty(tp, rtnl_held))
tp->deleting = true;
spin_unlock(&tp->lock);
return tp->deleting;
}
static void tcf_proto_mark_delete(struct tcf_proto *tp)
{
spin_lock(&tp->lock);
tp->deleting = true;
spin_unlock(&tp->lock);
}
static bool tcf_proto_is_deleting(struct tcf_proto *tp)
{
bool deleting;
spin_lock(&tp->lock);
deleting = tp->deleting;
spin_unlock(&tp->lock);
return deleting;
}
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
#define ASSERT_BLOCK_LOCKED(block) \
lockdep_assert_held(&(block)->lock)
struct tcf_filter_chain_list_item {
struct list_head list;
tcf_chain_head_change_t *chain_head_change;
void *chain_head_change_priv;
};
static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
u32 chain_index)
{
struct tcf_chain *chain;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
ASSERT_BLOCK_LOCKED(block);
chain = kzalloc(sizeof(*chain), GFP_KERNEL);
if (!chain)
return NULL;
list_add_tail(&chain->list, &block->chain_list);
mutex_init(&chain->filter_chain_lock);
chain->block = block;
chain->index = chain_index;
chain->refcnt = 1;
if (!chain->index)
block->chain0.chain = chain;
return chain;
}
static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
struct tcf_proto *tp_head)
{
if (item->chain_head_change)
item->chain_head_change(tp_head, item->chain_head_change_priv);
}
static void tcf_chain0_head_change(struct tcf_chain *chain,
struct tcf_proto *tp_head)
{
struct tcf_filter_chain_list_item *item;
struct tcf_block *block = chain->block;
if (chain->index)
return;
mutex_lock(&block->lock);
list_for_each_entry(item, &block->chain0.filter_chain_list, list)
tcf_chain_head_change_item(item, tp_head);
mutex_unlock(&block->lock);
}
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
/* Returns true if block can be safely freed. */
static bool tcf_chain_detach(struct tcf_chain *chain)
{
struct tcf_block *block = chain->block;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
ASSERT_BLOCK_LOCKED(block);
list_del(&chain->list);
if (!chain->index)
block->chain0.chain = NULL;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
if (list_empty(&block->chain_list) &&
refcount_read(&block->refcnt) == 0)
return true;
return false;
}
static void tcf_block_destroy(struct tcf_block *block)
{
mutex_destroy(&block->lock);
kfree_rcu(block, rcu);
}
static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
{
struct tcf_block *block = chain->block;
mutex_destroy(&chain->filter_chain_lock);
kfree_rcu(chain, rcu);
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
if (free_block)
tcf_block_destroy(block);
}
static void tcf_chain_hold(struct tcf_chain *chain)
{
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
ASSERT_BLOCK_LOCKED(chain->block);
++chain->refcnt;
}
static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
{
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
ASSERT_BLOCK_LOCKED(chain->block);
/* In case all the references are action references, this
* chain should not be shown to the user.
*/
return chain->refcnt == chain->action_refcnt;
}
static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
u32 chain_index)
{
struct tcf_chain *chain;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
ASSERT_BLOCK_LOCKED(block);
list_for_each_entry(chain, &block->chain_list, list) {
if (chain->index == chain_index)
return chain;
}
return NULL;
}
static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
u32 seq, u16 flags, int event, bool unicast);
static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
u32 chain_index, bool create,
bool by_act)
{
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
struct tcf_chain *chain = NULL;
bool is_first_reference;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
mutex_lock(&block->lock);
chain = tcf_chain_lookup(block, chain_index);
if (chain) {
tcf_chain_hold(chain);
} else {
if (!create)
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
goto errout;
chain = tcf_chain_create(block, chain_index);
if (!chain)
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
goto errout;
}
if (by_act)
++chain->action_refcnt;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
is_first_reference = chain->refcnt - chain->action_refcnt == 1;
mutex_unlock(&block->lock);
/* Send notification only in case we got the first
* non-action reference. Until then, the chain acts only as
* a placeholder for actions pointing to it and user ought
* not know about them.
*/
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
if (is_first_reference && !by_act)
tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
RTM_NEWCHAIN, false);
return chain;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
errout:
mutex_unlock(&block->lock);
return chain;
}
static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
bool create)
{
return __tcf_chain_get(block, chain_index, create, false);
}
struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
{
return __tcf_chain_get(block, chain_index, true, true);
}
EXPORT_SYMBOL(tcf_chain_get_by_act);
static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
void *tmplt_priv);
static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
void *tmplt_priv, u32 chain_index,
struct tcf_block *block, struct sk_buff *oskb,
u32 seq, u16 flags, bool unicast);
static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
bool explicitly_created)
{
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
struct tcf_block *block = chain->block;
const struct tcf_proto_ops *tmplt_ops;
bool free_block = false;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
unsigned int refcnt;
void *tmplt_priv;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
mutex_lock(&block->lock);
if (explicitly_created) {
if (!chain->explicitly_created) {
mutex_unlock(&block->lock);
return;
}
chain->explicitly_created = false;
}
if (by_act)
chain->action_refcnt--;
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
/* tc_chain_notify_delete can't be called while holding block lock.
* However, when block is unlocked chain can be changed concurrently, so
* save these to temporary variables.
*/
refcnt = --chain->refcnt;
tmplt_ops = chain->tmplt_ops;
tmplt_priv = chain->tmplt_priv;
/* The last dropped non-action reference will trigger notification. */
if (refcnt - chain->action_refcnt == 0 && !by_act) {
tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
block, NULL, 0, 0, false);
/* Last reference to chain, no need to lock. */
chain->flushing = false;
}
if (refcnt == 0)
free_block = tcf_chain_detach(chain);
mutex_unlock(&block->lock);
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
if (refcnt == 0) {
tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
tcf_chain_destroy(chain, free_block);
}
}
static void tcf_chain_put(struct tcf_chain *chain)
{
__tcf_chain_put(chain, false, false);
}
void tcf_chain_put_by_act(struct tcf_chain *chain)
{
__tcf_chain_put(chain, true, false);
}
EXPORT_SYMBOL(tcf_chain_put_by_act);
static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
{
__tcf_chain_put(chain, false, true);
}
static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
{
struct tcf_proto *tp, *tp_next;
mutex_lock(&chain->filter_chain_lock);
tp = tcf_chain_dereference(chain->filter_chain, chain);
RCU_INIT_POINTER(chain->filter_chain, NULL);
tcf_chain0_head_change(chain, NULL);
chain->flushing = true;
mutex_unlock(&chain->filter_chain_lock);
while (tp) {
tp_next = rcu_dereference_protected(tp->next, 1);
tcf_proto_put(tp, rtnl_held, NULL);
tp = tp_next;
}
}
static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
{
const struct Qdisc_class_ops *cops;
struct Qdisc *qdisc;
if (!dev_ingress_queue(dev))
return NULL;
qdisc = dev_ingress_queue(dev)->qdisc_sleeping;
if (!qdisc)
return NULL;
cops = qdisc->ops->cl_ops;
if (!cops)
return NULL;
if (!cops->tcf_block)
return NULL;
return cops->tcf_block(qdisc, TC_H_MIN_INGRESS, NULL);
}
static struct rhashtable indr_setup_block_ht;
struct tc_indr_block_dev {
struct rhash_head ht_node;
struct net_device *dev;
unsigned int refcnt;
struct list_head cb_list;
struct tcf_block *block;
};
struct tc_indr_block_cb {
struct list_head list;
void *cb_priv;
tc_indr_block_bind_cb_t *cb;
void *cb_ident;
};
static const struct rhashtable_params tc_indr_setup_block_ht_params = {
.key_offset = offsetof(struct tc_indr_block_dev, dev),
.head_offset = offsetof(struct tc_indr_block_dev, ht_node),
.key_len = sizeof(struct net_device *),
};
static struct tc_indr_block_dev *
tc_indr_block_dev_lookup(struct net_device *dev)
{
return rhashtable_lookup_fast(&indr_setup_block_ht, &dev,
tc_indr_setup_block_ht_params);
}
static struct tc_indr_block_dev *tc_indr_block_dev_get(struct net_device *dev)
{
struct tc_indr_block_dev *indr_dev;
indr_dev = tc_indr_block_dev_lookup(dev);
if (indr_dev)
goto inc_ref;
indr_dev = kzalloc(sizeof(*indr_dev), GFP_KERNEL);
if (!indr_dev)
return NULL;
INIT_LIST_HEAD(&indr_dev->cb_list);
indr_dev->dev = dev;
indr_dev->block = tc_dev_ingress_block(dev);
if (rhashtable_insert_fast(&indr_setup_block_ht, &indr_dev->ht_node,
tc_indr_setup_block_ht_params)) {
kfree(indr_dev);
return NULL;
}
inc_ref:
indr_dev->refcnt++;
return indr_dev;
}
static void tc_indr_block_dev_put(struct tc_indr_block_dev *indr_dev)
{
if (--indr_dev->refcnt)
return;
rhashtable_remove_fast(&indr_setup_block_ht, &indr_dev->ht_node,
tc_indr_setup_block_ht_params);
kfree(indr_dev);
}
static struct tc_indr_block_cb *
tc_indr_block_cb_lookup(struct tc_indr_block_dev *indr_dev,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
struct tc_indr_block_cb *indr_block_cb;
list_for_each_entry(indr_block_cb, &indr_dev->cb_list, list)
if (indr_block_cb->cb == cb &&
indr_block_cb->cb_ident == cb_ident)
return indr_block_cb;
return NULL;
}
static struct tc_indr_block_cb *
tc_indr_block_cb_add(struct tc_indr_block_dev *indr_dev, void *cb_priv,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
struct tc_indr_block_cb *indr_block_cb;
indr_block_cb = tc_indr_block_cb_lookup(indr_dev, cb, cb_ident);
if (indr_block_cb)
return ERR_PTR(-EEXIST);
indr_block_cb = kzalloc(sizeof(*indr_block_cb), GFP_KERNEL);
if (!indr_block_cb)
return ERR_PTR(-ENOMEM);
indr_block_cb->cb_priv = cb_priv;
indr_block_cb->cb = cb;
indr_block_cb->cb_ident = cb_ident;
list_add(&indr_block_cb->list, &indr_dev->cb_list);
return indr_block_cb;
}
static void tc_indr_block_cb_del(struct tc_indr_block_cb *indr_block_cb)
{
list_del(&indr_block_cb->list);
kfree(indr_block_cb);
}
static int tcf_block_setup(struct tcf_block *block,
struct flow_block_offload *bo);
static void tc_indr_block_ing_cmd(struct tc_indr_block_dev *indr_dev,
struct tc_indr_block_cb *indr_block_cb,
enum flow_block_command command)
{
struct flow_block_offload bo = {
.command = command,
.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS,
.net = dev_net(indr_dev->dev),
net: sched: Fix NULL-pointer dereference in tc_indr_block_ing_cmd() After recent refactoring of block offlads infrastructure, indr_dev->block pointer is dereferenced before it is verified to be non-NULL. Example stack trace where this behavior leads to NULL-pointer dereference error when creating vxlan dev on system with mlx5 NIC with offloads enabled: [ 1157.852938] ================================================================== [ 1157.866877] BUG: KASAN: null-ptr-deref in tc_indr_block_ing_cmd.isra.41+0x9c/0x160 [ 1157.880877] Read of size 4 at addr 0000000000000090 by task ip/3829 [ 1157.901637] CPU: 22 PID: 3829 Comm: ip Not tainted 5.2.0-rc6+ #488 [ 1157.914438] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 1157.929031] Call Trace: [ 1157.938318] dump_stack+0x9a/0xeb [ 1157.948362] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160 [ 1157.960262] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160 [ 1157.972082] __kasan_report+0x176/0x192 [ 1157.982513] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160 [ 1157.994348] kasan_report+0xe/0x20 [ 1158.004324] tc_indr_block_ing_cmd.isra.41+0x9c/0x160 [ 1158.015950] ? tcf_block_setup+0x430/0x430 [ 1158.026558] ? kasan_unpoison_shadow+0x30/0x40 [ 1158.037464] __tc_indr_block_cb_register+0x5f5/0xf20 [ 1158.049288] ? mlx5e_rep_indr_tc_block_unbind+0xa0/0xa0 [mlx5_core] [ 1158.062344] ? tc_indr_block_dev_put.part.47+0x5c0/0x5c0 [ 1158.074498] ? rdma_roce_rescan_device+0x20/0x20 [ib_core] [ 1158.086580] ? br_device_event+0x98/0x480 [bridge] [ 1158.097870] ? strcmp+0x30/0x50 [ 1158.107578] mlx5e_nic_rep_netdevice_event+0xdd/0x180 [mlx5_core] [ 1158.120212] notifier_call_chain+0x6d/0xa0 [ 1158.130753] register_netdevice+0x6fc/0x7e0 [ 1158.141322] ? netdev_change_features+0xa0/0xa0 [ 1158.152218] ? vxlan_config_apply+0x210/0x310 [vxlan] [ 1158.163593] __vxlan_dev_create+0x2ad/0x520 [vxlan] [ 1158.174770] ? vxlan_changelink+0x490/0x490 [vxlan] [ 1158.185870] ? rcu_read_unlock+0x60/0x60 [vxlan] [ 1158.196798] vxlan_newlink+0x99/0xf0 [vxlan] [ 1158.207303] ? __vxlan_dev_create+0x520/0x520 [vxlan] [ 1158.218601] ? rtnl_create_link+0x3d0/0x450 [ 1158.228900] __rtnl_newlink+0x8a7/0xb00 [ 1158.238701] ? stack_access_ok+0x35/0x80 [ 1158.248450] ? rtnl_link_unregister+0x1a0/0x1a0 [ 1158.258735] ? find_held_lock+0x6d/0xd0 [ 1158.268379] ? is_bpf_text_address+0x67/0xf0 [ 1158.278330] ? lock_acquire+0xc1/0x1f0 [ 1158.287686] ? is_bpf_text_address+0x5/0xf0 [ 1158.297449] ? is_bpf_text_address+0x86/0xf0 [ 1158.307310] ? kernel_text_address+0xec/0x100 [ 1158.317155] ? arch_stack_walk+0x92/0xe0 [ 1158.326497] ? __kernel_text_address+0xe/0x30 [ 1158.336213] ? unwind_get_return_address+0x2f/0x50 [ 1158.346267] ? create_prof_cpu_mask+0x20/0x20 [ 1158.355936] ? arch_stack_walk+0x92/0xe0 [ 1158.365117] ? stack_trace_save+0x8a/0xb0 [ 1158.374272] ? stack_trace_consume_entry+0x80/0x80 [ 1158.384226] ? match_held_lock+0x33/0x210 [ 1158.393216] ? kasan_unpoison_shadow+0x30/0x40 [ 1158.402593] rtnl_newlink+0x53/0x80 [ 1158.410925] rtnetlink_rcv_msg+0x3a5/0x600 [ 1158.419777] ? validate_linkmsg+0x400/0x400 [ 1158.428620] ? find_held_lock+0x6d/0xd0 [ 1158.437117] ? match_held_lock+0x1b/0x210 [ 1158.445760] ? validate_linkmsg+0x400/0x400 [ 1158.454642] netlink_rcv_skb+0xc7/0x1f0 [ 1158.463150] ? netlink_ack+0x470/0x470 [ 1158.471538] ? netlink_deliver_tap+0x1f3/0x5a0 [ 1158.480607] netlink_unicast+0x2ae/0x350 [ 1158.489099] ? netlink_attachskb+0x340/0x340 [ 1158.497935] ? _copy_from_iter_full+0xde/0x3b0 [ 1158.506945] ? __virt_addr_valid+0xb6/0xf0 [ 1158.515578] ? __check_object_size+0x159/0x240 [ 1158.524515] netlink_sendmsg+0x4d3/0x630 [ 1158.532879] ? netlink_unicast+0x350/0x350 [ 1158.541400] ? netlink_unicast+0x350/0x350 [ 1158.549805] sock_sendmsg+0x94/0xa0 [ 1158.557561] ___sys_sendmsg+0x49d/0x570 [ 1158.565625] ? copy_msghdr_from_user+0x210/0x210 [ 1158.574457] ? __fput+0x1e2/0x330 [ 1158.581948] ? __kasan_slab_free+0x130/0x180 [ 1158.590407] ? kmem_cache_free+0xb6/0x2d0 [ 1158.598574] ? mark_lock+0xc7/0x790 [ 1158.606177] ? task_work_run+0xcf/0x100 [ 1158.614165] ? exit_to_usermode_loop+0x102/0x110 [ 1158.622954] ? __lock_acquire+0x963/0x1ee0 [ 1158.631199] ? lockdep_hardirqs_on+0x260/0x260 [ 1158.639777] ? match_held_lock+0x1b/0x210 [ 1158.647918] ? lockdep_hardirqs_on+0x260/0x260 [ 1158.656501] ? match_held_lock+0x1b/0x210 [ 1158.664643] ? __fget_light+0xa6/0xe0 [ 1158.672423] ? __sys_sendmsg+0xd2/0x150 [ 1158.680334] __sys_sendmsg+0xd2/0x150 [ 1158.688063] ? __ia32_sys_shutdown+0x30/0x30 [ 1158.696435] ? lock_downgrade+0x2e0/0x2e0 [ 1158.704541] ? mark_held_locks+0x1a/0x90 [ 1158.712611] ? mark_held_locks+0x1a/0x90 [ 1158.720619] ? do_syscall_64+0x1e/0x2c0 [ 1158.728530] do_syscall_64+0x78/0x2c0 [ 1158.736254] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1158.745414] RIP: 0033:0x7f62d505cb87 [ 1158.753070] Code: 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 80 00 00 00 00 8b 05 6a 2b 2c 00 48 63 d2 48 63 ff 85 c0 75 18 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 59 f3 c3 0f 1f 80 00 00[87/1817] 48 89 f3 48 [ 1158.780924] RSP: 002b:00007fffd9832268 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 1158.793204] RAX: ffffffffffffffda RBX: 000000005d26048f RCX: 00007f62d505cb87 [ 1158.805111] RDX: 0000000000000000 RSI: 00007fffd98322d0 RDI: 0000000000000003 [ 1158.817055] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006 [ 1158.828987] R10: 00007f62d50ce260 R11: 0000000000000246 R12: 0000000000000001 [ 1158.840909] R13: 000000000067e540 R14: 0000000000000000 R15: 000000000067ed20 [ 1158.852873] ================================================================== Introduce new function tcf_block_non_null_shared() that verifies block pointer before dereferencing it to obtain index. Use the function in tc_indr_block_ing_cmd() to prevent NULL pointer dereference. Fixes: 955bcb6ea0df ("drivers: net: use flow block API") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-10 19:12:29 +02:00
.block_shared = tcf_block_non_null_shared(indr_dev->block),
};
INIT_LIST_HEAD(&bo.cb_list);
if (!indr_dev->block)
return;
bo.block = &indr_dev->block->flow_block;
indr_block_cb->cb(indr_dev->dev, indr_block_cb->cb_priv, TC_SETUP_BLOCK,
&bo);
tcf_block_setup(indr_dev->block, &bo);
}
int __tc_indr_block_cb_register(struct net_device *dev, void *cb_priv,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
struct tc_indr_block_cb *indr_block_cb;
struct tc_indr_block_dev *indr_dev;
int err;
indr_dev = tc_indr_block_dev_get(dev);
if (!indr_dev)
return -ENOMEM;
indr_block_cb = tc_indr_block_cb_add(indr_dev, cb_priv, cb, cb_ident);
err = PTR_ERR_OR_ZERO(indr_block_cb);
if (err)
goto err_dev_put;
tc_indr_block_ing_cmd(indr_dev, indr_block_cb, FLOW_BLOCK_BIND);
return 0;
err_dev_put:
tc_indr_block_dev_put(indr_dev);
return err;
}
EXPORT_SYMBOL_GPL(__tc_indr_block_cb_register);
int tc_indr_block_cb_register(struct net_device *dev, void *cb_priv,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
int err;
rtnl_lock();
err = __tc_indr_block_cb_register(dev, cb_priv, cb, cb_ident);
rtnl_unlock();
return err;
}
EXPORT_SYMBOL_GPL(tc_indr_block_cb_register);
void __tc_indr_block_cb_unregister(struct net_device *dev,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
struct tc_indr_block_cb *indr_block_cb;
struct tc_indr_block_dev *indr_dev;
indr_dev = tc_indr_block_dev_lookup(dev);
if (!indr_dev)
return;
indr_block_cb = tc_indr_block_cb_lookup(indr_dev, cb, cb_ident);
if (!indr_block_cb)
return;
/* Send unbind message if required to free any block cbs. */
tc_indr_block_ing_cmd(indr_dev, indr_block_cb, FLOW_BLOCK_UNBIND);
tc_indr_block_cb_del(indr_block_cb);
tc_indr_block_dev_put(indr_dev);
}
EXPORT_SYMBOL_GPL(__tc_indr_block_cb_unregister);
void tc_indr_block_cb_unregister(struct net_device *dev,
tc_indr_block_bind_cb_t *cb, void *cb_ident)
{
rtnl_lock();
__tc_indr_block_cb_unregister(dev, cb, cb_ident);
rtnl_unlock();
}
EXPORT_SYMBOL_GPL(tc_indr_block_cb_unregister);
static void tc_indr_block_call(struct tcf_block *block, struct net_device *dev,
struct tcf_block_ext_info *ei,
enum flow_block_command command,
struct netlink_ext_ack *extack)
{
struct tc_indr_block_cb *indr_block_cb;
struct tc_indr_block_dev *indr_dev;
struct flow_block_offload bo = {
.command = command,
.binder_type = ei->binder_type,
.net = dev_net(dev),
.block = &block->flow_block,
.block_shared = tcf_block_shared(block),
.extack = extack,
};
INIT_LIST_HEAD(&bo.cb_list);
indr_dev = tc_indr_block_dev_lookup(dev);
if (!indr_dev)
return;
indr_dev->block = command == FLOW_BLOCK_BIND ? block : NULL;
list_for_each_entry(indr_block_cb, &indr_dev->cb_list, list)
indr_block_cb->cb(dev, indr_block_cb->cb_priv, TC_SETUP_BLOCK,
&bo);
tcf_block_setup(block, &bo);
}
static bool tcf_block_offload_in_use(struct tcf_block *block)
{
return block->offloadcnt;
}
static int tcf_block_offload_cmd(struct tcf_block *block,
struct net_device *dev,
struct tcf_block_ext_info *ei,
enum flow_block_command command,
struct netlink_ext_ack *extack)
{
struct flow_block_offload bo = {};
int err;
bo.net = dev_net(dev);
bo.command = command;
bo.binder_type = ei->binder_type;
bo.block = &block->flow_block;
bo.block_shared = tcf_block_shared(block);
bo.extack = extack;
INIT_LIST_HEAD(&bo.cb_list);
err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
if (err < 0)
return err;
return tcf_block_setup(block, &bo);
}
static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
struct tcf_block_ext_info *ei,
struct netlink_ext_ack *extack)
{
struct net_device *dev = q->dev_queue->dev;
int err;
if (!dev->netdev_ops->ndo_setup_tc)
goto no_offload_dev_inc;
/* If tc offload feature is disabled and the block we try to bind
* to already has some offloaded filters, forbid to bind.
*/
if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) {
NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
return -EOPNOTSUPP;
}
err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack);
if (err == -EOPNOTSUPP)
goto no_offload_dev_inc;
if (err)
return err;
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
return 0;
no_offload_dev_inc:
if (tcf_block_offload_in_use(block))
return -EOPNOTSUPP;
block->nooffloaddevcnt++;
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
return 0;
}
static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
struct tcf_block_ext_info *ei)
{
struct net_device *dev = q->dev_queue->dev;
int err;
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
if (!dev->netdev_ops->ndo_setup_tc)
goto no_offload_dev_dec;
err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
if (err == -EOPNOTSUPP)
goto no_offload_dev_dec;
return;
no_offload_dev_dec:
WARN_ON(block->nooffloaddevcnt-- == 0);
}
static int
tcf_chain0_head_change_cb_add(struct tcf_block *block,
struct tcf_block_ext_info *ei,
struct netlink_ext_ack *extack)
{
struct tcf_filter_chain_list_item *item;
struct tcf_chain *chain0;
item = kmalloc(sizeof(*item), GFP_KERNEL);
if (!item) {
NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
return -ENOMEM;
}
item->chain_head_change = ei->chain_head_change;
item->chain_head_change_priv = ei->chain_head_change_priv;
mutex_lock(&block->lock);
chain0 = block->chain0.chain;
if (chain0)
tcf_chain_hold(chain0);
else
list_add(&item->list, &block->chain0.filter_chain_list);
mutex_unlock(&block->lock);
if (chain0) {
struct tcf_proto *tp_head;
mutex_lock(&chain0->filter_chain_lock);
tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
if (tp_head)
tcf_chain_head_change_item(item, tp_head);
mutex_lock(&block->lock);
list_add(&item->list, &block->chain0.filter_chain_list);
mutex_unlock(&block->lock);
mutex_unlock(&chain0->filter_chain_lock);
tcf_chain_put(chain0);
}
return 0;
}
static void
tcf_chain0_head_change_cb_del(struct tcf_block *block,
struct tcf_block_ext_info *ei)
{
struct tcf_filter_chain_list_item *item;
mutex_lock(&block->lock);
list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
(item->chain_head_change == ei->chain_head_change &&
item->chain_head_change_priv == ei->chain_head_change_priv)) {
if (block->chain0.chain)
tcf_chain_head_change_item(item, NULL);
list_del(&item->list);
mutex_unlock(&block->lock);
kfree(item);
return;
}
}
mutex_unlock(&block->lock);
WARN_ON(1);
}
struct tcf_net {
spinlock_t idr_lock; /* Protects idr */
struct idr idr;
};
static unsigned int tcf_net_id;
static int tcf_block_insert(struct tcf_block *block, struct net *net,
struct netlink_ext_ack *extack)
{
struct tcf_net *tn = net_generic(net, tcf_net_id);
int err;
idr_preload(GFP_KERNEL);
spin_lock(&tn->idr_lock);
err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
GFP_NOWAIT);
spin_unlock(&tn->idr_lock);
idr_preload_end();
return err;
}
static void tcf_block_remove(struct tcf_block *block, struct net *net)
{
struct tcf_net *tn = net_generic(net, tcf_net_id);
spin_lock(&tn->idr_lock);
idr_remove(&tn->idr, block->index);
spin_unlock(&tn->idr_lock);
}
static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
u32 block_index,
struct netlink_ext_ack *extack)
{
struct tcf_block *block;
block = kzalloc(sizeof(*block), GFP_KERNEL);
if (!block) {
NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
return ERR_PTR(-ENOMEM);
}
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
mutex_init(&block->lock);
flow_block_init(&block->flow_block);
INIT_LIST_HEAD(&block->chain_list);
INIT_LIST_HEAD(&block->owner_list);
INIT_LIST_HEAD(&block->chain0.filter_chain_list);
refcount_set(&block->refcnt, 1);
block->net = net;
block->index = block_index;
/* Don't store q pointer for blocks which are shared */
if (!tcf_block_shared(block))
block->q = q;
return block;
}
static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
{
struct tcf_net *tn = net_generic(net, tcf_net_id);
return idr_find(&tn->idr, block_index);
}
static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
{
struct tcf_block *block;
rcu_read_lock();
block = tcf_block_lookup(net, block_index);
if (block && !refcount_inc_not_zero(&block->refcnt))
block = NULL;
rcu_read_unlock();
return block;
}
static struct tcf_chain *
__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
{
mutex_lock(&block->lock);
if (chain)
chain = list_is_last(&chain->list, &block->chain_list) ?
NULL : list_next_entry(chain, list);
else
chain = list_first_entry_or_null(&block->chain_list,
struct tcf_chain, list);
/* skip all action-only chains */
while (chain && tcf_chain_held_by_acts_only(chain))
chain = list_is_last(&chain->list, &block->chain_list) ?
NULL : list_next_entry(chain, list);
if (chain)
tcf_chain_hold(chain);
mutex_unlock(&block->lock);
return chain;
}
/* Function to be used by all clients that want to iterate over all chains on
* block. It properly obtains block->lock and takes reference to chain before
* returning it. Users of this function must be tolerant to concurrent chain
* insertion/deletion or ensure that no concurrent chain modification is
* possible. Note that all netlink dump callbacks cannot guarantee to provide
* consistent dump because rtnl lock is released each time skb is filled with
* data and sent to user-space.
*/
struct tcf_chain *
tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
{
struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
if (chain)
tcf_chain_put(chain);
return chain_next;
}
EXPORT_SYMBOL(tcf_get_next_chain);
static struct tcf_proto *
__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
{
u32 prio = 0;
ASSERT_RTNL();
mutex_lock(&chain->filter_chain_lock);
if (!tp) {
tp = tcf_chain_dereference(chain->filter_chain, chain);
} else if (tcf_proto_is_deleting(tp)) {
/* 'deleting' flag is set and chain->filter_chain_lock was
* unlocked, which means next pointer could be invalid. Restart
* search.
*/
prio = tp->prio + 1;
tp = tcf_chain_dereference(chain->filter_chain, chain);
for (; tp; tp = tcf_chain_dereference(tp->next, chain))
if (!tp->deleting && tp->prio >= prio)
break;
} else {
tp = tcf_chain_dereference(tp->next, chain);
}
if (tp)
tcf_proto_get(tp);
mutex_unlock(&chain->filter_chain_lock);
return tp;
}
/* Function to be used by all clients that want to iterate over all tp's on
* chain. Users of this function must be tolerant to concurrent tp
* insertion/deletion or ensure that no concurrent chain modification is
* possible. Note that all netlink dump callbacks cannot guarantee to provide
* consistent dump because rtnl lock is released each time skb is filled with
* data and sent to user-space.
*/
struct tcf_proto *
tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
bool rtnl_held)
{
struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
if (tp)
tcf_proto_put(tp, rtnl_held, NULL);
return tp_next;
}
EXPORT_SYMBOL(tcf_get_next_proto);
static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
{
struct tcf_chain *chain;
/* Last reference to block. At this point chains cannot be added or
* removed concurrently.
*/
for (chain = tcf_get_next_chain(block, NULL);
chain;
chain = tcf_get_next_chain(block, chain)) {
tcf_chain_put_explicitly_created(chain);
tcf_chain_flush(chain, rtnl_held);
}
}
/* Lookup Qdisc and increments its reference counter.
* Set parent, if necessary.
*/
static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
u32 *parent, int ifindex, bool rtnl_held,
struct netlink_ext_ack *extack)
{
const struct Qdisc_class_ops *cops;
struct net_device *dev;
int err = 0;
if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
return 0;
rcu_read_lock();
/* Find link */
dev = dev_get_by_index_rcu(net, ifindex);
if (!dev) {
rcu_read_unlock();
return -ENODEV;
}
/* Find qdisc */
if (!*parent) {
*q = dev->qdisc;
*parent = (*q)->handle;
} else {
*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
if (!*q) {
NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
err = -EINVAL;
goto errout_rcu;
}
}
*q = qdisc_refcount_inc_nz(*q);
if (!*q) {
NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
err = -EINVAL;
goto errout_rcu;
}
/* Is it classful? */
cops = (*q)->ops->cl_ops;
if (!cops) {
NL_SET_ERR_MSG(extack, "Qdisc not classful");
err = -EINVAL;
goto errout_qdisc;
}
if (!cops->tcf_block) {
NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
err = -EOPNOTSUPP;
goto errout_qdisc;
}
errout_rcu:
/* At this point we know that qdisc is not noop_qdisc,
* which means that qdisc holds a reference to net_device
* and we hold a reference to qdisc, so it is safe to release
* rcu read lock.
*/
rcu_read_unlock();
return err;
errout_qdisc:
rcu_read_unlock();
if (rtnl_held)
qdisc_put(*q);
else
qdisc_put_unlocked(*q);
*q = NULL;
return err;
}
static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
int ifindex, struct netlink_ext_ack *extack)
{
if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
return 0;
/* Do we search for filter, attached to class? */
if (TC_H_MIN(parent)) {
const struct Qdisc_class_ops *cops = q->ops->cl_ops;
*cl = cops->find(q, parent);
if (*cl == 0) {
NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
return -ENOENT;
}
}
return 0;
}
static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
unsigned long cl, int ifindex,
u32 block_index,
struct netlink_ext_ack *extack)
{
struct tcf_block *block;
if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
block = tcf_block_refcnt_get(net, block_index);
if (!block) {
NL_SET_ERR_MSG(extack, "Block of given index was not found");
return ERR_PTR(-EINVAL);
}
} else {
const struct Qdisc_class_ops *cops = q->ops->cl_ops;
block = cops->tcf_block(q, cl, extack);
if (!block)
return ERR_PTR(-EINVAL);
if (tcf_block_shared(block)) {
NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
return ERR_PTR(-EOPNOTSUPP);
}
/* Always take reference to block in order to support execution
* of rules update path of cls API without rtnl lock. Caller
* must release block when it is finished using it. 'if' block
* of this conditional obtain reference to block by calling
* tcf_block_refcnt_get().
*/
refcount_inc(&block->refcnt);
}
return block;
}
static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
struct tcf_block_ext_info *ei, bool rtnl_held)
{
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
/* Flushing/putting all chains will cause the block to be
* deallocated when last chain is freed. However, if chain_list
* is empty, block has to be manually deallocated. After block
* reference counter reached 0, it is no longer possible to
* increment it or add new chains to block.
*/
bool free_block = list_empty(&block->chain_list);
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
mutex_unlock(&block->lock);
if (tcf_block_shared(block))
tcf_block_remove(block, block->net);
if (q)
tcf_block_offload_unbind(block, q, ei);
if (free_block)
net: sched: protect block state with mutex Currently, tcf_block doesn't use any synchronization mechanisms to protect critical sections that manage lifetime of its chains. block->chain_list and multiple variables in tcf_chain that control its lifetime assume external synchronization provided by global rtnl lock. Converting chain reference counting to atomic reference counters is not possible because cls API uses multiple counters and flags to control chain lifetime, so all of them must be synchronized in chain get/put code. Use single per-block lock to protect block data and manage lifetime of all chains on the block. Always take block->lock when accessing chain_list. Chain get and put modify chain lifetime-management data and parent block's chain_list, so take the lock in these functions. Verify block->lock state with assertions in functions that expect to be called with the lock taken and are called from multiple places. Take block->lock when accessing filter_chain_list. In order to allow parallel update of rules on single block, move all calls to classifiers outside of critical sections protected by new block->lock. Rearrange chain get and put functions code to only access protected chain data while holding block lock: - Rearrange code to only access chain reference counter and chain action reference counter while holding block lock. - Extract code that requires block->lock from tcf_chain_destroy() into standalone tcf_chain_destroy() function that is called by __tcf_chain_put() in same critical section that changes chain reference counters. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 09:55:32 +01:00
tcf_block_destroy(block);
else
tcf_block_flush_all_chains(block, rtnl_held);
} else if (q) {
tcf_block_offload_unbind(block, q, ei);
}
}
static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
{
__tcf_block_put(block, NULL, NULL, rtnl_held);
}
/* Find tcf block.
* Set q, parent, cl when appropriate.
*/
static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
u32 *parent, unsigned long *cl,
int ifindex, u32 block_index,
struct netlink_ext_ack *extack)
{
struct tcf_block *block;
int err = 0;
ASSERT_RTNL();
err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
if (err)
goto errout;
err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
if (err)
goto errout_qdisc;
block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
if (IS_ERR(block)) {
err = PTR_ERR(block);
goto errout_qdisc;
}
return block;
errout_qdisc:
if (*q)
qdisc_put(*q);
errout:
*q = NULL;
return ERR_PTR(err);
}
static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
bool rtnl_held)
{
if (!IS_ERR_OR_NULL(block))
tcf_block_refcnt_put(block, rtnl_held);
if (q) {
if (rtnl_held)
qdisc_put(q);
else
qdisc_put_unlocked(q);
}
}
struct tcf_block_owner_item {
struct list_head list;
struct Qdisc *q;
enum flow_block_binder_type binder_type;
};
static void
tcf_block_owner_netif_keep_dst(struct tcf_block *block,
struct Qdisc *q,
enum flow_block_binder_type binder_type)
{
if (block->keep_dst &&
binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
netif_keep_dst(qdisc_dev(q));
}
void tcf_block_netif_keep_dst(struct tcf_block *block)
{
struct tcf_block_owner_item *item;
block->keep_dst = true;
list_for_each_entry(item, &block->owner_list, list)
tcf_block_owner_netif_keep_dst(block, item->q,
item->binder_type);
}
EXPORT_SYMBOL(tcf_block_netif_keep_dst);
static int tcf_block_owner_add(struct tcf_block *block,
struct Qdisc *q,
enum flow_block_binder_type binder_type)
{
struct tcf_block_owner_item *item;
item = kmalloc(sizeof(*item), GFP_KERNEL);
if (!item)
return -ENOMEM;
item->q = q;
item->binder_type = binder_type;
list_add(&item->list, &block->owner_list);
return 0;
}
static void tcf_block_owner_del(struct tcf_block *block,
struct Qdisc *q,
enum flow_block_binder_type binder_type)
{
struct tcf_block_owner_item *item;
list_for_each_entry(item, &block->owner_list, list) {
if (item->q == q && item->binder_type == binder_type) {
list_del(&item->list);
kfree(item);
return;
}
}
WARN_ON(1);
}
int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
struct tcf_block_ext_info *ei,
struct netlink_ext_ack *extack)
{
struct net *net = qdisc_net(q);
struct tcf_block *block = NULL;
int err;
if (ei->block_index)
/* block_index not 0 means the shared block is requested */
block = tcf_block_refcnt_get(net, ei->block_index);
if (!block) {
block = tcf_block_create(net, q, ei->block_index, extack);
if (IS_ERR(block))
return PTR_ERR(block);
if (tcf_block_shared(block)) {
err = tcf_block_insert(block, net, extack);
if (err)
goto err_block_insert;
}
}
err = tcf_block_owner_add(block, q, ei->binder_type);
if (err)
goto err_block_owner_add;
tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
err = tcf_chain0_head_change_cb_add(block, ei, extack);
if (err)
goto err_chain0_head_change_cb_add;
err = tcf_block_offload_bind(block, q, ei, extack);
if (err)
goto err_block_offload_bind;
*p_block = block;
return 0;
err_block_offload_bind:
tcf_chain0_head_change_cb_del(block, ei);
err_chain0_head_change_cb_add:
tcf_block_owner_del(block, q, ei->binder_type);
err_block_owner_add:
err_block_insert:
tcf_block_refcnt_put(block, true);
return err;
}
EXPORT_SYMBOL(tcf_block_get_ext);
static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
{
struct tcf_proto __rcu **p_filter_chain = priv;
rcu_assign_pointer(*p_filter_chain, tp_head);
}
int tcf_block_get(struct tcf_block **p_block,
struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
struct netlink_ext_ack *extack)
{
struct tcf_block_ext_info ei = {
.chain_head_change = tcf_chain_head_change_dflt,
.chain_head_change_priv = p_filter_chain,
};
WARN_ON(!p_filter_chain);
return tcf_block_get_ext(p_block, q, &ei, extack);
}
EXPORT_SYMBOL(tcf_block_get);
/* XXX: Standalone actions are not allowed to jump to any chain, and bound
* actions should be all removed after flushing.
*/
void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
struct tcf_block_ext_info *ei)
{
if (!block)
return;
tcf_chain0_head_change_cb_del(block, ei);
tcf_block_owner_del(block, q, ei->binder_type);
__tcf_block_put(block, q, ei, true);
}
EXPORT_SYMBOL(tcf_block_put_ext);
void tcf_block_put(struct tcf_block *block)
{
struct tcf_block_ext_info ei = {0, };
if (!block)
return;
tcf_block_put_ext(block, block->q, &ei);
}
EXPORT_SYMBOL(tcf_block_put);
static int
tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
void *cb_priv, bool add, bool offload_in_use,
struct netlink_ext_ack *extack)
{
struct tcf_chain *chain, *chain_prev;
struct tcf_proto *tp, *tp_prev;
int err;
for (chain = __tcf_get_next_chain(block, NULL);
chain;
chain_prev = chain,
chain = __tcf_get_next_chain(block, chain),
tcf_chain_put(chain_prev)) {
for (tp = __tcf_get_next_proto(chain, NULL); tp;
tp_prev = tp,
tp = __tcf_get_next_proto(chain, tp),
tcf_proto_put(tp_prev, true, NULL)) {
if (tp->ops->reoffload) {
err = tp->ops->reoffload(tp, add, cb, cb_priv,
extack);
if (err && add)
goto err_playback_remove;
} else if (add && offload_in_use) {
err = -EOPNOTSUPP;
NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
goto err_playback_remove;
}
}
}
return 0;
err_playback_remove:
tcf_proto_put(tp, true, NULL);
tcf_chain_put(chain);
tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
extack);
return err;
}
static int tcf_block_bind(struct tcf_block *block,
struct flow_block_offload *bo)
{
struct flow_block_cb *block_cb, *next;
int err, i = 0;
list_for_each_entry(block_cb, &bo->cb_list, list) {
err = tcf_block_playback_offloads(block, block_cb->cb,
block_cb->cb_priv, true,
tcf_block_offload_in_use(block),
bo->extack);
if (err)
goto err_unroll;
i++;
}
list_splice(&bo->cb_list, &block->flow_block.cb_list);
return 0;
err_unroll:
list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
if (i-- > 0) {
list_del(&block_cb->list);
tcf_block_playback_offloads(block, block_cb->cb,
block_cb->cb_priv, false,
tcf_block_offload_in_use(block),
NULL);
}
flow_block_cb_free(block_cb);
}
return err;
}
static void tcf_block_unbind(struct tcf_block *block,
struct flow_block_offload *bo)
{
struct flow_block_cb *block_cb, *next;
list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
tcf_block_playback_offloads(block, block_cb->cb,
block_cb->cb_priv, false,
tcf_block_offload_in_use(block),
NULL);
list_del(&block_cb->list);
flow_block_cb_free(block_cb);
}
}
static int tcf_block_setup(struct tcf_block *block,
struct flow_block_offload *bo)
{
int err;
switch (bo->command) {
case FLOW_BLOCK_BIND:
err = tcf_block_bind(block, bo);
break;
case FLOW_BLOCK_UNBIND:
err = 0;
tcf_block_unbind(block, bo);
break;
default:
WARN_ON_ONCE(1);
err = -EOPNOTSUPP;
}
return err;
}
/* Main classifier routine: scans classifier chain attached
* to this qdisc, (optionally) tests for protocol and asks
* specific classifiers.
*/
int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
struct tcf_result *res, bool compat_mode)
{
#ifdef CONFIG_NET_CLS_ACT
const int max_reclassify_loop = 4;
const struct tcf_proto *orig_tp = tp;
const struct tcf_proto *first_tp;
int limit = 0;
reclassify:
#endif
for (; tp; tp = rcu_dereference_bh(tp->next)) {
__be16 protocol = tc_skb_protocol(skb);
int err;
if (tp->protocol != protocol &&
tp->protocol != htons(ETH_P_ALL))
continue;
err = tp->classify(skb, tp, res);
#ifdef CONFIG_NET_CLS_ACT
if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
first_tp = orig_tp;
goto reset;
} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
first_tp = res->goto_tp;
goto reset;
}
#endif
if (err >= 0)
return err;
}
return TC_ACT_UNSPEC; /* signal: continue lookup */
#ifdef CONFIG_NET_CLS_ACT
reset:
if (unlikely(limit++ >= max_reclassify_loop)) {
net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
tp->chain->block->index,
tp->prio & 0xffff,
ntohs(tp->protocol));
return TC_ACT_SHOT;
}
tp = first_tp;
goto reclassify;
#endif
}
EXPORT_SYMBOL(tcf_classify);
struct tcf_chain_info {
struct tcf_proto __rcu **pprev;
struct tcf_proto __rcu *next;
};
static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
struct tcf_chain_info *chain_info)
{
return tcf_chain_dereference(*chain_info->pprev, chain);
}
static int tcf_chain_tp_insert(struct tcf_chain *chain,
struct tcf_chain_info *chain_info,
struct tcf_proto *tp)
{
if (chain->flushing)
return -EAGAIN;
if (*chain_info->pprev == chain->filter_chain)
tcf_chain0_head_change(chain, tp);
tcf_proto_get(tp);
RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
rcu_assign_pointer(*chain_info->pprev, tp);
return 0;
}
static void tcf_chain_tp_remove(struct tcf_chain *chain,
struct tcf_chain_info *chain_info,
struct tcf_proto *tp)
{
struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
tcf_proto_mark_delete(tp);
if (tp == chain->filter_chain)
tcf_chain0_head_change(chain, next);
RCU_INIT_POINTER(*chain_info->pprev, next);
}
static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
struct tcf_chain_info *chain_info,
u32 protocol, u32 prio,
bool prio_allocate);
/* Try to insert new proto.
* If proto with specified priority already exists, free new proto
* and return existing one.
*/
static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
struct tcf_proto *tp_new,
u32 protocol, u32 prio,
bool rtnl_held)
{
struct tcf_chain_info chain_info;
struct tcf_proto *tp;
int err = 0;
mutex_lock(&chain->filter_chain_lock);
tp = tcf_chain_tp_find(chain, &chain_info,
protocol, prio, false);
if (!tp)
err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
mutex_unlock(&chain->filter_chain_lock);
if (tp) {
tcf_proto_destroy(tp_new, rtnl_held, NULL);
tp_new = tp;
} else if (err) {
tcf_proto_destroy(tp_new, rtnl_held, NULL);
tp_new = ERR_PTR(err);
}
return tp_new;
}
static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
struct tcf_proto *tp, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct tcf_chain_info chain_info;
struct tcf_proto *tp_iter;
struct tcf_proto **pprev;
struct tcf_proto *next;
mutex_lock(&chain->filter_chain_lock);
/* Atomically find and remove tp from chain. */
for (pprev = &chain->filter_chain;
(tp_iter = tcf_chain_dereference(*pprev, chain));
pprev = &tp_iter->next) {
if (tp_iter == tp) {
chain_info.pprev = pprev;
chain_info.next = tp_iter->next;
WARN_ON(tp_iter->deleting);
break;
}
}
/* Verify that tp still exists and no new filters were inserted
* concurrently.
* Mark tp for deletion if it is empty.
*/
if (!tp_iter || !tcf_proto_check_delete(tp, rtnl_held)) {
mutex_unlock(&chain->filter_chain_lock);
return;
}
next = tcf_chain_dereference(chain_info.next, chain);
if (tp == chain->filter_chain)
tcf_chain0_head_change(chain, next);
RCU_INIT_POINTER(*chain_info.pprev, next);
mutex_unlock(&chain->filter_chain_lock);
tcf_proto_put(tp, rtnl_held, extack);
}
static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
struct tcf_chain_info *chain_info,
u32 protocol, u32 prio,
bool prio_allocate)
{
struct tcf_proto **pprev;
struct tcf_proto *tp;
/* Check the chain for existence of proto-tcf with this priority */
for (pprev = &chain->filter_chain;
(tp = tcf_chain_dereference(*pprev, chain));
pprev = &tp->next) {
if (tp->prio >= prio) {
if (tp->prio == prio) {
if (prio_allocate ||
(tp->protocol != protocol && protocol))
return ERR_PTR(-EINVAL);
} else {
tp = NULL;
}
break;
}
}
chain_info->pprev = pprev;
if (tp) {
chain_info->next = tp->next;
tcf_proto_get(tp);
} else {
chain_info->next = NULL;
}
return tp;
}
static int tcf_fill_node(struct net *net, struct sk_buff *skb,
struct tcf_proto *tp, struct tcf_block *block,
struct Qdisc *q, u32 parent, void *fh,
u32 portid, u32 seq, u16 flags, int event,
bool rtnl_held)
{
struct tcmsg *tcm;
struct nlmsghdr *nlh;
unsigned char *b = skb_tail_pointer(skb);
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
if (!nlh)
goto out_nlmsg_trim;
tcm = nlmsg_data(nlh);
tcm->tcm_family = AF_UNSPEC;
tcm->tcm__pad1 = 0;
tcm->tcm__pad2 = 0;
if (q) {
tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
tcm->tcm_parent = parent;
} else {
tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
tcm->tcm_block_index = block->index;
}
tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
goto nla_put_failure;
if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
goto nla_put_failure;
if (!fh) {
tcm->tcm_handle = 0;
} else {
if (tp->ops->dump &&
tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
goto nla_put_failure;
}
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
return skb->len;
out_nlmsg_trim:
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static int tfilter_notify(struct net *net, struct sk_buff *oskb,
struct nlmsghdr *n, struct tcf_proto *tp,
struct tcf_block *block, struct Qdisc *q,
u32 parent, void *fh, int event, bool unicast,
bool rtnl_held)
{
struct sk_buff *skb;
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
int err = 0;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
n->nlmsg_seq, n->nlmsg_flags, event,
rtnl_held) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
if (unicast)
err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
else
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (err > 0)
err = 0;
return err;
}
static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
struct nlmsghdr *n, struct tcf_proto *tp,
struct tcf_block *block, struct Qdisc *q,
u32 parent, void *fh, bool unicast, bool *last,
bool rtnl_held, struct netlink_ext_ack *extack)
{
struct sk_buff *skb;
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
int err;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
rtnl_held) <= 0) {
NL_SET_ERR_MSG(extack, "Failed to build del event notification");
kfree_skb(skb);
return -EINVAL;
}
err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
if (err) {
kfree_skb(skb);
return err;
}
if (unicast)
err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
else
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
n->nlmsg_flags & NLM_F_ECHO);
if (err < 0)
NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
if (err > 0)
err = 0;
return err;
}
static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
struct tcf_block *block, struct Qdisc *q,
u32 parent, struct nlmsghdr *n,
struct tcf_chain *chain, int event,
bool rtnl_held)
{
struct tcf_proto *tp;
for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
tfilter_notify(net, oskb, n, tp, block,
q, parent, NULL, event, false, rtnl_held);
}
static void tfilter_put(struct tcf_proto *tp, void *fh)
{
if (tp->ops->put && fh)
tp->ops->put(tp, fh);
}
static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct tcmsg *t;
u32 protocol;
u32 prio;
bool prio_allocate;
u32 parent;
u32 chain_index;
struct Qdisc *q = NULL;
struct tcf_chain_info chain_info;
struct tcf_chain *chain = NULL;
struct tcf_block *block;
struct tcf_proto *tp;
unsigned long cl;
void *fh;
int err;
net, sched: fix soft lockup in tc_classify Shahar reported a soft lockup in tc_classify(), where we run into an endless loop when walking the classifier chain due to tp->next == tp which is a state we should never run into. The issue only seems to trigger under load in the tc control path. What happens is that in tc_ctl_tfilter(), thread A allocates a new tp, initializes it, sets tp_created to 1, and calls into tp->ops->change() with it. In that classifier callback we had to unlock/lock the rtnl mutex and returned with -EAGAIN. One reason why we need to drop there is, for example, that we need to request an action module to be loaded. This happens via tcf_exts_validate() -> tcf_action_init/_1() meaning after we loaded and found the requested action, we need to redo the whole request so we don't race against others. While we had to unlock rtnl in that time, thread B's request was processed next on that CPU. Thread B added a new tp instance successfully to the classifier chain. When thread A returned grabbing the rtnl mutex again, propagating -EAGAIN and destroying its tp instance which never got linked, we goto replay and redo A's request. This time when walking the classifier chain in tc_ctl_tfilter() for checking for existing tp instances we had a priority match and found the tp instance that was created and linked by thread B. Now calling again into tp->ops->change() with that tp was successful and returned without error. tp_created was never cleared in the second round, thus kernel thinks that we need to link it into the classifier chain (once again). tp and *back point to the same object due to the match we had earlier on. Thus for thread B's already public tp, we reset tp->next to tp itself and link it into the chain, which eventually causes the mentioned endless loop in tc_classify() once a packet hits the data path. Fix is to clear tp_created at the beginning of each request, also when we replay it. On the paths that can cause -EAGAIN we already destroy the original tp instance we had and on replay we really need to start from scratch. It seems that this issue was first introduced in commit 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup"). Fixes: 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup") Reported-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-21 18:04:11 +01:00
int tp_created;
bool rtnl_held = false;
if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
return -EPERM;
replay:
net, sched: fix soft lockup in tc_classify Shahar reported a soft lockup in tc_classify(), where we run into an endless loop when walking the classifier chain due to tp->next == tp which is a state we should never run into. The issue only seems to trigger under load in the tc control path. What happens is that in tc_ctl_tfilter(), thread A allocates a new tp, initializes it, sets tp_created to 1, and calls into tp->ops->change() with it. In that classifier callback we had to unlock/lock the rtnl mutex and returned with -EAGAIN. One reason why we need to drop there is, for example, that we need to request an action module to be loaded. This happens via tcf_exts_validate() -> tcf_action_init/_1() meaning after we loaded and found the requested action, we need to redo the whole request so we don't race against others. While we had to unlock rtnl in that time, thread B's request was processed next on that CPU. Thread B added a new tp instance successfully to the classifier chain. When thread A returned grabbing the rtnl mutex again, propagating -EAGAIN and destroying its tp instance which never got linked, we goto replay and redo A's request. This time when walking the classifier chain in tc_ctl_tfilter() for checking for existing tp instances we had a priority match and found the tp instance that was created and linked by thread B. Now calling again into tp->ops->change() with that tp was successful and returned without error. tp_created was never cleared in the second round, thus kernel thinks that we need to link it into the classifier chain (once again). tp and *back point to the same object due to the match we had earlier on. Thus for thread B's already public tp, we reset tp->next to tp itself and link it into the chain, which eventually causes the mentioned endless loop in tc_classify() once a packet hits the data path. Fix is to clear tp_created at the beginning of each request, also when we replay it. On the paths that can cause -EAGAIN we already destroy the original tp instance we had and on replay we really need to start from scratch. It seems that this issue was first introduced in commit 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup"). Fixes: 12186be7d2e1 ("net_cls: fix unconfigured struct tcf_proto keeps chaining and avoid kernel panic when we use cls_cgroup") Reported-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Shahar Klein <shahark@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-21 18:04:11 +01:00
tp_created = 0;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
rtm_tca_policy, extack);
if (err < 0)
return err;
t = nlmsg_data(n);
protocol = TC_H_MIN(t->tcm_info);
prio = TC_H_MAJ(t->tcm_info);
prio_allocate = false;
parent = t->tcm_parent;
tp = NULL;
cl = 0;
block = NULL;
if (prio == 0) {
/* If no priority is provided by the user,
* we allocate one.
*/
if (n->nlmsg_flags & NLM_F_CREATE) {
prio = TC_H_MAKE(0x80000000U, 0U);
prio_allocate = true;
} else {
NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
return -ENOENT;
net, cls: allow for deleting all filters for given parent Add a possibility where the user can just specify the parent and all filters under that parent are then being purged. Currently, for example for scripting, one needs to specify pref/prio to have a well-defined number for 'tc filter del' command for addressing the previously created instance or additionally filter handle in case of priorities being the same. Improve usage by allowing the option for tc to specify the parent and removing the whole chain for that given parent. Example usage after patch, no tc changes required: # tc qdisc replace dev foo clsact # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter show dev foo egress filter protocol all pref 49151 bpf filter protocol all pref 49151 bpf handle 0x1 bpf.o:[classifier] direct-action filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 bpf.o:[classifier] direct-action # tc filter del dev foo egress # tc filter show dev foo egress # Previously, RTM_DELTFILTER requests with invalid prio of 0 were rejected, so only netlink requests with RTM_NEWTFILTER and NLM_F_CREATE flag were allowed where the kernel would auto-generate a pref/prio. We can piggyback on that and use prio of 0 as a wildcard for requests of RTM_DELTFILTER. For notifying tc netlink monitoring users (e.g. libnl uses this for caching), there are two options, that is, sending individual tfilter_notify() notifications for each tcf_proto, or sending a single one indicating wildcard removal. I tried both and there are pros and cons for each, eventually I decided for sending individual tfilter_notify(), so that user space can support this seamlessly and there won't be a mess of changing each and every application to make sure expectations from the kernel won't break when they don't understand single notification. Since linear chains don't really scale, I expect only a handful of classifiers to be attached at max for a given parent anyway. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10 23:10:22 +02:00
}
}
/* Find head of filter chain. */
err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
if (err)
return err;
/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
* block is shared (no qdisc found), qdisc is not unlocked, classifier
* type is not specified, classifier is not unlocked.
*/
if (rtnl_held ||
(q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
!tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
rtnl_held = true;
rtnl_lock();
}
err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
if (err)
goto errout;
block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
extack);
if (IS_ERR(block)) {
err = PTR_ERR(block);
goto errout;
}
chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
if (chain_index > TC_ACT_EXT_VAL_MASK) {
NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
err = -EINVAL;
goto errout;
}
chain = tcf_chain_get(block, chain_index, true);
if (!chain) {
NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
err = -ENOMEM;
net, cls: allow for deleting all filters for given parent Add a possibility where the user can just specify the parent and all filters under that parent are then being purged. Currently, for example for scripting, one needs to specify pref/prio to have a well-defined number for 'tc filter del' command for addressing the previously created instance or additionally filter handle in case of priorities being the same. Improve usage by allowing the option for tc to specify the parent and removing the whole chain for that given parent. Example usage after patch, no tc changes required: # tc qdisc replace dev foo clsact # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter add dev foo egress bpf da obj ./bpf.o # tc filter show dev foo egress filter protocol all pref 49151 bpf filter protocol all pref 49151 bpf handle 0x1 bpf.o:[classifier] direct-action filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 bpf.o:[classifier] direct-action # tc filter del dev foo egress # tc filter show dev foo egress # Previously, RTM_DELTFILTER requests with invalid prio of 0 were rejected, so only netlink requests with RTM_NEWTFILTER and NLM_F_CREATE flag were allowed where the kernel would auto-generate a pref/prio. We can piggyback on that and use prio of 0 as a wildcard for requests of RTM_DELTFILTER. For notifying tc netlink monitoring users (e.g. libnl uses this for caching), there are two options, that is, sending individual tfilter_notify() notifications for each tcf_proto, or sending a single one indicating wildcard removal. I tried both and there are pros and cons for each, eventually I decided for sending individual tfilter_notify(), so that user space can support this seamlessly and there won't be a mess of changing each and every application to make sure expectations from the kernel won't break when they don't understand single notification. Since linear chains don't really scale, I expect only a handful of classifiers to be attached at max for a given parent anyway. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10 23:10:22 +02:00
goto errout;
}
mutex_lock(&chain->filter_chain_lock);
tp = tcf_chain_tp_find(chain, &chain_info, protocol,
prio, prio_allocate);
if (IS_ERR(tp)) {
NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
err = PTR_ERR(tp);
goto errout_locked;
}
if (tp == NULL) {
struct tcf_proto *tp_new = NULL;
if (chain->flushing) {
err = -EAGAIN;
goto errout_locked;
}
/* Proto-tcf does not exist, create new one */
if (tca[TCA_KIND] == NULL || !protocol) {
NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
err = -EINVAL;
goto errout_locked;
}
if (!(n->nlmsg_flags & NLM_F_CREATE)) {
NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
err = -ENOENT;
goto errout_locked;
}
if (prio_allocate)
prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
&chain_info));
mutex_unlock(&chain->filter_chain_lock);
tp_new = tcf_proto_create(nla_data(tca[TCA_KIND]),
protocol, prio, chain, rtnl_held,
extack);
if (IS_ERR(tp_new)) {
err = PTR_ERR(tp_new);
goto errout_tp;
}
tp_created = 1;
tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
rtnl_held);
if (IS_ERR(tp)) {
err = PTR_ERR(tp);
goto errout_tp;
}
} else {
mutex_unlock(&chain->filter_chain_lock);
}
if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
err = -EINVAL;
goto errout;
}
fh = tp->ops->get(tp, t->tcm_handle);
if (!fh) {
if (!(n->nlmsg_flags & NLM_F_CREATE)) {
NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
err = -ENOENT;
goto errout;
}
} else if (n->nlmsg_flags & NLM_F_EXCL) {
tfilter_put(tp, fh);
NL_SET_ERR_MSG(extack, "Filter already exists");
err = -EEXIST;
goto errout;
}
if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
err = -EINVAL;
goto errout;
}
err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
rtnl_held, extack);
if (err == 0) {
tfilter_notify(net, skb, n, tp, block, q, parent, fh,
RTM_NEWTFILTER, false, rtnl_held);
tfilter_put(tp, fh);
net: sched: verify that q!=NULL before setting q->flags In function int tc_new_tfilter() q pointer can be NULL when adding filter on a shared block. With recent change that resets TCQ_F_CAN_BYPASS after filter creation, following NULL pointer dereference happens in case parent block is shared: [ 212.925060] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 212.925445] #PF: supervisor write access in kernel mode [ 212.925709] #PF: error_code(0x0002) - not-present page [ 212.925965] PGD 8000000827923067 P4D 8000000827923067 PUD 827924067 PMD 0 [ 212.926302] Oops: 0002 [#1] SMP KASAN PTI [ 212.926539] CPU: 18 PID: 2617 Comm: tc Tainted: G B 5.2.0+ #512 [ 212.926938] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 212.927364] RIP: 0010:tc_new_tfilter+0x698/0xd40 [ 212.927633] Code: 74 0d 48 85 c0 74 08 48 89 ef e8 03 aa 62 00 48 8b 84 24 a0 00 00 00 48 8d 78 10 48 89 44 24 18 e8 4d 0c 6b ff 48 8b 44 24 18 <83> 60 10 f b 48 85 ed 0f 85 3d fe ff ff e9 4f fe ff ff e8 81 26 f8 [ 212.928607] RSP: 0018:ffff88884fd5f5d8 EFLAGS: 00010296 [ 212.928905] RAX: 0000000000000000 RBX: 0000000000000000 RCX: dffffc0000000000 [ 212.929201] RDX: 0000000000000007 RSI: 0000000000000004 RDI: 0000000000000297 [ 212.929402] RBP: ffff88886bedd600 R08: ffffffffb91d4b51 R09: fffffbfff7616e4d [ 212.929609] R10: fffffbfff7616e4c R11: ffffffffbb0b7263 R12: ffff88886bc61040 [ 212.929803] R13: ffff88884fd5f950 R14: ffffc900039c5000 R15: ffff88835e927680 [ 212.929999] FS: 00007fe7c50b6480(0000) GS:ffff88886f980000(0000) knlGS:0000000000000000 [ 212.930235] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 212.930394] CR2: 0000000000000010 CR3: 000000085bd04002 CR4: 00000000001606e0 [ 212.930588] Call Trace: [ 212.930682] ? tc_del_tfilter+0xa40/0xa40 [ 212.930811] ? __lock_acquire+0x5b5/0x2460 [ 212.930948] ? find_held_lock+0x85/0xa0 [ 212.931081] ? tc_del_tfilter+0xa40/0xa40 [ 212.931201] rtnetlink_rcv_msg+0x4ab/0x5f0 [ 212.931332] ? rtnl_dellink+0x490/0x490 [ 212.931454] ? lockdep_hardirqs_on+0x260/0x260 [ 212.931589] ? netlink_deliver_tap+0xab/0x5a0 [ 212.931717] ? match_held_lock+0x1b/0x240 [ 212.931844] netlink_rcv_skb+0xd0/0x200 [ 212.931958] ? rtnl_dellink+0x490/0x490 [ 212.932079] ? netlink_ack+0x440/0x440 [ 212.932205] ? netlink_deliver_tap+0x161/0x5a0 [ 212.932335] ? lock_downgrade+0x360/0x360 [ 212.932457] ? lock_acquire+0xe5/0x210 [ 212.932579] netlink_unicast+0x296/0x350 [ 212.932705] ? netlink_attachskb+0x390/0x390 [ 212.932834] ? _copy_from_iter_full+0xe0/0x3a0 [ 212.932976] netlink_sendmsg+0x394/0x600 [ 212.937998] ? netlink_unicast+0x350/0x350 [ 212.943033] ? move_addr_to_kernel.part.0+0x90/0x90 [ 212.948115] ? netlink_unicast+0x350/0x350 [ 212.953185] sock_sendmsg+0x96/0xa0 [ 212.958099] ___sys_sendmsg+0x482/0x520 [ 212.962881] ? match_held_lock+0x1b/0x240 [ 212.967618] ? copy_msghdr_from_user+0x250/0x250 [ 212.972337] ? lock_downgrade+0x360/0x360 [ 212.976973] ? rwlock_bug.part.0+0x60/0x60 [ 212.981548] ? __mod_node_page_state+0x1f/0xa0 [ 212.986060] ? match_held_lock+0x1b/0x240 [ 212.990567] ? find_held_lock+0x85/0xa0 [ 212.994989] ? do_user_addr_fault+0x349/0x5b0 [ 212.999387] ? lock_downgrade+0x360/0x360 [ 213.003713] ? find_held_lock+0x85/0xa0 [ 213.007972] ? __fget_light+0xa1/0xf0 [ 213.012143] ? sockfd_lookup_light+0x91/0xb0 [ 213.016165] __sys_sendmsg+0xba/0x130 [ 213.020040] ? __sys_sendmsg_sock+0xb0/0xb0 [ 213.023870] ? handle_mm_fault+0x337/0x470 [ 213.027592] ? page_fault+0x8/0x30 [ 213.031316] ? lockdep_hardirqs_off+0xbe/0x100 [ 213.034999] ? mark_held_locks+0x24/0x90 [ 213.038671] ? do_syscall_64+0x1e/0xe0 [ 213.042297] do_syscall_64+0x74/0xe0 [ 213.045828] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 213.049354] RIP: 0033:0x7fe7c527c7b8 [ 213.052792] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f 0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 54 [ 213.060269] RSP: 002b:00007ffc3f7908a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 213.064144] RAX: ffffffffffffffda RBX: 000000005d34716f RCX: 00007fe7c527c7b8 [ 213.068094] RDX: 0000000000000000 RSI: 00007ffc3f790910 RDI: 0000000000000003 [ 213.072109] RBP: 0000000000000000 R08: 0000000000000001 R09: 00007fe7c5340cc0 [ 213.076113] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000080 [ 213.080146] R13: 0000000000480640 R14: 0000000000000080 R15: 0000000000000000 [ 213.084147] Modules linked in: act_gact cls_flower sch_ingress nfsv3 nfs_acl nfs lockd grace fscache bridge stp llc sunrpc intel_rapl_msr intel_rapl_common [<1;69;32Msb_edac rdma_ucm rdma_cm x86_pkg_temp_thermal iw_cm intel_powerclamp ib_cm coretemp kvm_intel kvm irqbypass mlx5_ib ib_uverbs ib_core crct10dif_pclmul crc32_pc lmul crc32c_intel ghash_clmulni_intel mlx5_core intel_cstate intel_uncore iTCO_wdt igb iTCO_vendor_support mlxfw mei_me ptp ses intel_rapl_perf mei pcspkr ipmi _ssif i2c_i801 joydev enclosure pps_core lpc_ich ioatdma wmi dca ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad ast i2c_algo_bit drm_vram_helpe r ttm drm_kms_helper drm mpt3sas raid_class scsi_transport_sas [ 213.112326] CR2: 0000000000000010 [ 213.117429] ---[ end trace adb58eb0a4ee6283 ]--- Verify that q pointer is not NULL before setting the 'flags' field. Fixes: 3f05e6886a59 ("net_sched: unset TCQ_F_CAN_BYPASS when adding filters") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-21 16:44:12 +02:00
/* q pointer is NULL for shared blocks */
if (q)
q->flags &= ~TCQ_F_CAN_BYPASS;
}
errout:
if (err && tp_created)
tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
errout_tp:
if (chain) {
if (tp && !IS_ERR(tp))
tcf_proto_put(tp, rtnl_held, NULL);
if (!tp_created)
tcf_chain_put(chain);
}
tcf_block_release(q, block, rtnl_held);
if (rtnl_held)
rtnl_unlock();
if (err == -EAGAIN) {
/* Take rtnl lock in case EAGAIN is caused by concurrent flush
* of target chain.
*/
rtnl_held = true;
/* Replay the request. */
goto replay;
}
return err;
errout_locked:
mutex_unlock(&chain->filter_chain_lock);
goto errout;
}
static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct tcmsg *t;
u32 protocol;
u32 prio;
u32 parent;
u32 chain_index;
struct Qdisc *q = NULL;
struct tcf_chain_info chain_info;
struct tcf_chain *chain = NULL;
struct tcf_block *block = NULL;
struct tcf_proto *tp = NULL;
unsigned long cl = 0;
void *fh = NULL;
int err;
bool rtnl_held = false;
if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
return -EPERM;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
rtm_tca_policy, extack);
if (err < 0)
return err;
t = nlmsg_data(n);
protocol = TC_H_MIN(t->tcm_info);
prio = TC_H_MAJ(t->tcm_info);
parent = t->tcm_parent;
if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
return -ENOENT;
}
/* Find head of filter chain. */
err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
if (err)
return err;
/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
* found), qdisc is not unlocked, classifier type is not specified,
* classifier is not unlocked.
*/
if (!prio ||
(q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
!tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
rtnl_held = true;
rtnl_lock();
}
err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
if (err)
goto errout;
block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
extack);
if (IS_ERR(block)) {
err = PTR_ERR(block);
goto errout;
}
chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
if (chain_index > TC_ACT_EXT_VAL_MASK) {
NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
err = -EINVAL;
goto errout;
}
chain = tcf_chain_get(block, chain_index, false);
if (!chain) {
/* User requested flush on non-existent chain. Nothing to do,
* so just return success.
*/
if (prio == 0) {
err = 0;
goto errout;
}
NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
err = -ENOENT;
goto errout;
}
if (prio == 0) {
tfilter_notify_chain(net, skb, block, q, parent, n,
chain, RTM_DELTFILTER, rtnl_held);
tcf_chain_flush(chain, rtnl_held);
err = 0;
goto errout;
}
mutex_lock(&chain->filter_chain_lock);
tp = tcf_chain_tp_find(chain, &chain_info, protocol,
prio, false);
if (!tp || IS_ERR(tp)) {
NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
err = tp ? PTR_ERR(tp) : -ENOENT;
goto errout_locked;
} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
err = -EINVAL;
goto errout_locked;
} else if (t->tcm_handle == 0) {
tcf_chain_tp_remove(chain, &chain_info, tp);
mutex_unlock(&chain->filter_chain_lock);
tcf_proto_put(tp, rtnl_held, NULL);
tfilter_notify(net, skb, n, tp, block, q, parent, fh,
RTM_DELTFILTER, false, rtnl_held);
err = 0;
goto errout;
}
mutex_unlock(&chain->filter_chain_lock);
fh = tp->ops->get(tp, t->tcm_handle);
if (!fh) {
NL_SET_ERR_MSG(extack, "Specified filter handle not found");
err = -ENOENT;
} else {
bool last;
err = tfilter_del_notify(net, skb, n, tp, block,
q, parent, fh, false, &last,
rtnl_held, extack);
if (err)
goto errout;
if (last)
tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
}
errout:
if (chain) {
if (tp && !IS_ERR(tp))
tcf_proto_put(tp, rtnl_held, NULL);
tcf_chain_put(chain);
}
tcf_block_release(q, block, rtnl_held);
if (rtnl_held)
rtnl_unlock();
return err;
errout_locked:
mutex_unlock(&chain->filter_chain_lock);
goto errout;
}
static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct tcmsg *t;
u32 protocol;
u32 prio;
u32 parent;
u32 chain_index;
struct Qdisc *q = NULL;
struct tcf_chain_info chain_info;
struct tcf_chain *chain = NULL;
struct tcf_block *block = NULL;
struct tcf_proto *tp = NULL;
unsigned long cl = 0;
void *fh = NULL;
int err;
bool rtnl_held = false;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
rtm_tca_policy, extack);
if (err < 0)
return err;
t = nlmsg_data(n);
protocol = TC_H_MIN(t->tcm_info);
prio = TC_H_MAJ(t->tcm_info);
parent = t->tcm_parent;
if (prio == 0) {
NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
return -ENOENT;
}
/* Find head of filter chain. */
err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
if (err)
return err;
/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
* unlocked, classifier type is not specified, classifier is not
* unlocked.
*/
if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
!tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
rtnl_held = true;
rtnl_lock();
}
err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
if (err)
goto errout;
block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
extack);
if (IS_ERR(block)) {
err = PTR_ERR(block);
goto errout;
}
chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
if (chain_index > TC_ACT_EXT_VAL_MASK) {
NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
err = -EINVAL;
goto errout;
}
chain = tcf_chain_get(block, chain_index, false);
if (!chain) {
NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
err = -EINVAL;
goto errout;
}
mutex_lock(&chain->filter_chain_lock);
tp = tcf_chain_tp_find(chain, &chain_info, protocol,
prio, false);
mutex_unlock(&chain->filter_chain_lock);
if (!tp || IS_ERR(tp)) {
NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
err = tp ? PTR_ERR(tp) : -ENOENT;
goto errout;
} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
err = -EINVAL;
goto errout;
}
fh = tp->ops->get(tp, t->tcm_handle);
if (!fh) {
NL_SET_ERR_MSG(extack, "Specified filter handle not found");
err = -ENOENT;
} else {
err = tfilter_notify(net, skb, n, tp, block, q, parent,
fh, RTM_NEWTFILTER, true, rtnl_held);
if (err < 0)
NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
}
tfilter_put(tp, fh);
errout:
if (chain) {
if (tp && !IS_ERR(tp))
tcf_proto_put(tp, rtnl_held, NULL);
tcf_chain_put(chain);
}
tcf_block_release(q, block, rtnl_held);
if (rtnl_held)
rtnl_unlock();
return err;
}
struct tcf_dump_args {
struct tcf_walker w;
struct sk_buff *skb;
struct netlink_callback *cb;
struct tcf_block *block;
struct Qdisc *q;
u32 parent;
};
static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
{
struct tcf_dump_args *a = (void *)arg;
struct net *net = sock_net(a->skb->sk);
return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
n, NETLINK_CB(a->cb->skb).portid,
a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
RTM_NEWTFILTER, true);
}
static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
struct sk_buff *skb, struct netlink_callback *cb,
long index_start, long *p_index)
{
struct net *net = sock_net(skb->sk);
struct tcf_block *block = chain->block;
struct tcmsg *tcm = nlmsg_data(cb->nlh);
struct tcf_proto *tp, *tp_prev;
struct tcf_dump_args arg;
for (tp = __tcf_get_next_proto(chain, NULL);
tp;
tp_prev = tp,
tp = __tcf_get_next_proto(chain, tp),
tcf_proto_put(tp_prev, true, NULL),
(*p_index)++) {
if (*p_index < index_start)
continue;
if (TC_H_MAJ(tcm->tcm_info) &&
TC_H_MAJ(tcm->tcm_info) != tp->prio)
continue;
if (TC_H_MIN(tcm->tcm_info) &&
TC_H_MIN(tcm->tcm_info) != tp->protocol)
continue;
if (*p_index > index_start)
memset(&cb->args[1], 0,
sizeof(cb->args) - sizeof(cb->args[0]));
if (cb->args[1] == 0) {
if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
RTM_NEWTFILTER, true) <= 0)
goto errout;
cb->args[1] = 1;
}
if (!tp->ops->walk)
continue;
arg.w.fn = tcf_node_dump;
arg.skb = skb;
arg.cb = cb;
arg.block = block;
arg.q = q;
arg.parent = parent;
arg.w.stop = 0;
arg.w.skip = cb->args[1] - 1;
arg.w.count = 0;
arg.w.cookie = cb->args[2];
tp->ops->walk(tp, &arg.w, true);
cb->args[2] = arg.w.cookie;
cb->args[1] = arg.w.count + 1;
if (arg.w.stop)
goto errout;
}
return true;
errout:
tcf_proto_put(tp, true, NULL);
return false;
}
/* called with RTNL */
static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
{
struct tcf_chain *chain, *chain_prev;
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct Qdisc *q = NULL;
struct tcf_block *block;
struct tcmsg *tcm = nlmsg_data(cb->nlh);
long index_start;
long index;
u32 parent;
int err;
if (nlmsg_len(cb->nlh) < sizeof(*tcm))
return skb->len;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
NULL, cb->extack);
if (err)
return err;
if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
if (!block)
goto out;
/* If we work with block index, q is NULL and parent value
* will never be used in the following code. The check
* in tcf_fill_node prevents it. However, compiler does not
* see that far, so set parent to zero to silence the warning
* about parent being uninitialized.
*/
parent = 0;
} else {
const struct Qdisc_class_ops *cops;
struct net_device *dev;
unsigned long cl = 0;
dev = __dev_get_by_index(net, tcm->tcm_ifindex);
if (!dev)
return skb->len;
parent = tcm->tcm_parent;
if (!parent) {
q = dev->qdisc;
parent = q->handle;
} else {
q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
}
if (!q)
goto out;
cops = q->ops->cl_ops;
if (!cops)
goto out;
if (!cops->tcf_block)
goto out;
if (TC_H_MIN(tcm->tcm_parent)) {
cl = cops->find(q, tcm->tcm_parent);
if (cl == 0)
goto out;
}
block = cops->tcf_block(q, cl, NULL);
if (!block)
goto out;
if (tcf_block_shared(block))
q = NULL;
}
index_start = cb->args[0];
index = 0;
for (chain = __tcf_get_next_chain(block, NULL);
chain;
chain_prev = chain,
chain = __tcf_get_next_chain(block, chain),
tcf_chain_put(chain_prev)) {
if (tca[TCA_CHAIN] &&
nla_get_u32(tca[TCA_CHAIN]) != chain->index)
continue;
if (!tcf_chain_dump(chain, q, parent, skb, cb,
index_start, &index)) {
tcf_chain_put(chain);
err = -EMSGSIZE;
break;
}
}
if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
tcf_block_refcnt_put(block, true);
cb->args[0] = index;
out:
/* If we did no progress, the error (EMSGSIZE) is real */
if (skb->len == 0 && err)
return err;
return skb->len;
}
static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
void *tmplt_priv, u32 chain_index,
struct net *net, struct sk_buff *skb,
struct tcf_block *block,
u32 portid, u32 seq, u16 flags, int event)
{
unsigned char *b = skb_tail_pointer(skb);
const struct tcf_proto_ops *ops;
struct nlmsghdr *nlh;
struct tcmsg *tcm;
void *priv;
ops = tmplt_ops;
priv = tmplt_priv;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
if (!nlh)
goto out_nlmsg_trim;
tcm = nlmsg_data(nlh);
tcm->tcm_family = AF_UNSPEC;
tcm->tcm__pad1 = 0;
tcm->tcm__pad2 = 0;
tcm->tcm_handle = 0;
if (block->q) {
tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
tcm->tcm_parent = block->q->handle;
} else {
tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
tcm->tcm_block_index = block->index;
}
if (nla_put_u32(skb, TCA_CHAIN, chain_index))
goto nla_put_failure;
if (ops) {
if (nla_put_string(skb, TCA_KIND, ops->kind))
goto nla_put_failure;
if (ops->tmplt_dump(skb, net, priv) < 0)
goto nla_put_failure;
}
nlh->nlmsg_len = skb_tail_pointer(skb) - b;
return skb->len;
out_nlmsg_trim:
nla_put_failure:
nlmsg_trim(skb, b);
return -EMSGSIZE;
}
static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
u32 seq, u16 flags, int event, bool unicast)
{
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
struct tcf_block *block = chain->block;
struct net *net = block->net;
struct sk_buff *skb;
int err = 0;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
chain->index, net, skb, block, portid,
seq, flags, event) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
if (unicast)
err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
else
err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
flags & NLM_F_ECHO);
if (err > 0)
err = 0;
return err;
}
static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
void *tmplt_priv, u32 chain_index,
struct tcf_block *block, struct sk_buff *oskb,
u32 seq, u16 flags, bool unicast)
{
u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
struct net *net = block->net;
struct sk_buff *skb;
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
kfree_skb(skb);
return -EINVAL;
}
if (unicast)
return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
}
static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
struct nlattr **tca,
struct netlink_ext_ack *extack)
{
const struct tcf_proto_ops *ops;
void *tmplt_priv;
/* If kind is not set, user did not specify template. */
if (!tca[TCA_KIND])
return 0;
ops = tcf_proto_lookup_ops(nla_data(tca[TCA_KIND]), true, extack);
if (IS_ERR(ops))
return PTR_ERR(ops);
if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
return -EOPNOTSUPP;
}
tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
if (IS_ERR(tmplt_priv)) {
module_put(ops->owner);
return PTR_ERR(tmplt_priv);
}
chain->tmplt_ops = ops;
chain->tmplt_priv = tmplt_priv;
return 0;
}
static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
void *tmplt_priv)
{
/* If template ops are set, no work to do for us. */
if (!tmplt_ops)
return;
tmplt_ops->tmplt_destroy(tmplt_priv);
module_put(tmplt_ops->owner);
}
/* Add/delete/get a chain */
static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct tcmsg *t;
u32 parent;
u32 chain_index;
struct Qdisc *q = NULL;
struct tcf_chain *chain = NULL;
struct tcf_block *block;
unsigned long cl;
int err;
if (n->nlmsg_type != RTM_GETCHAIN &&
!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
return -EPERM;
replay:
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
rtm_tca_policy, extack);
if (err < 0)
return err;
t = nlmsg_data(n);
parent = t->tcm_parent;
cl = 0;
block = tcf_block_find(net, &q, &parent, &cl,
t->tcm_ifindex, t->tcm_block_index, extack);
if (IS_ERR(block))
return PTR_ERR(block);
chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
if (chain_index > TC_ACT_EXT_VAL_MASK) {
NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
err = -EINVAL;
goto errout_block;
}
mutex_lock(&block->lock);
chain = tcf_chain_lookup(block, chain_index);
if (n->nlmsg_type == RTM_NEWCHAIN) {
if (chain) {
if (tcf_chain_held_by_acts_only(chain)) {
/* The chain exists only because there is
* some action referencing it.
*/
tcf_chain_hold(chain);
} else {
NL_SET_ERR_MSG(extack, "Filter chain already exists");
err = -EEXIST;
goto errout_block_locked;
}
} else {
if (!(n->nlmsg_flags & NLM_F_CREATE)) {
NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
err = -ENOENT;
goto errout_block_locked;
}
chain = tcf_chain_create(block, chain_index);
if (!chain) {
NL_SET_ERR_MSG(extack, "Failed to create filter chain");
err = -ENOMEM;
goto errout_block_locked;
}
}
} else {
if (!chain || tcf_chain_held_by_acts_only(chain)) {
NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
err = -EINVAL;
goto errout_block_locked;
}
tcf_chain_hold(chain);
}
if (n->nlmsg_type == RTM_NEWCHAIN) {
/* Modifying chain requires holding parent block lock. In case
* the chain was successfully added, take a reference to the
* chain. This ensures that an empty chain does not disappear at
* the end of this function.
*/
tcf_chain_hold(chain);
chain->explicitly_created = true;
}
mutex_unlock(&block->lock);
switch (n->nlmsg_type) {
case RTM_NEWCHAIN:
err = tc_chain_tmplt_add(chain, net, tca, extack);
if (err) {
tcf_chain_put_explicitly_created(chain);
goto errout;
}
tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
RTM_NEWCHAIN, false);
break;
case RTM_DELCHAIN:
tfilter_notify_chain(net, skb, block, q, parent, n,
chain, RTM_DELTFILTER, true);
/* Flush the chain first as the user requested chain removal. */
tcf_chain_flush(chain, true);
/* In case the chain was successfully deleted, put a reference
* to the chain previously taken during addition.
*/
tcf_chain_put_explicitly_created(chain);
break;
case RTM_GETCHAIN:
err = tc_chain_notify(chain, skb, n->nlmsg_seq,
n->nlmsg_seq, n->nlmsg_type, true);
if (err < 0)
NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
break;
default:
err = -EOPNOTSUPP;
NL_SET_ERR_MSG(extack, "Unsupported message type");
goto errout;
}
errout:
tcf_chain_put(chain);
errout_block:
tcf_block_release(q, block, true);
if (err == -EAGAIN)
/* Replay the request. */
goto replay;
return err;
errout_block_locked:
mutex_unlock(&block->lock);
goto errout_block;
}
/* called with RTNL */
static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tca[TCA_MAX + 1];
struct Qdisc *q = NULL;
struct tcf_block *block;
struct tcmsg *tcm = nlmsg_data(cb->nlh);
struct tcf_chain *chain;
long index_start;
long index;
u32 parent;
int err;
if (nlmsg_len(cb->nlh) < sizeof(*tcm))
return skb->len;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 14:07:28 +02:00
err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
rtm_tca_policy, cb->extack);
if (err)
return err;
if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
if (!block)
goto out;
/* If we work with block index, q is NULL and parent value
* will never be used in the following code. The check
* in tcf_fill_node prevents it. However, compiler does not
* see that far, so set parent to zero to silence the warning
* about parent being uninitialized.
*/
parent = 0;
} else {
const struct Qdisc_class_ops *cops;
struct net_device *dev;
unsigned long cl = 0;
dev = __dev_get_by_index(net, tcm->tcm_ifindex);
if (!dev)
return skb->len;
parent = tcm->tcm_parent;
if (!parent) {
q = dev->qdisc;
parent = q->handle;
} else {
q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
}
if (!q)
goto out;
cops = q->ops->cl_ops;
if (!cops)
goto out;
if (!cops->tcf_block)
goto out;
if (TC_H_MIN(tcm->tcm_parent)) {
cl = cops->find(q, tcm->tcm_parent);
if (cl == 0)
goto out;
}
block = cops->tcf_block(q, cl, NULL);
if (!block)
goto out;
if (tcf_block_shared(block))
q = NULL;
}
index_start = cb->args[0];
index = 0;
mutex_lock(&block->lock);
list_for_each_entry(chain, &block->chain_list, list) {
if ((tca[TCA_CHAIN] &&
nla_get_u32(tca[TCA_CHAIN]) != chain->index))
continue;
if (index < index_start) {
index++;
continue;
}
if (tcf_chain_held_by_acts_only(chain))
continue;
err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
chain->index, net, skb, block,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
RTM_NEWCHAIN);
if (err <= 0)
break;
index++;
}
mutex_unlock(&block->lock);
if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
tcf_block_refcnt_put(block, true);
cb->args[0] = index;
out:
/* If we did no progress, the error (EMSGSIZE) is real */
if (skb->len == 0 && err)
return err;
return skb->len;
}
void tcf_exts_destroy(struct tcf_exts *exts)
{
#ifdef CONFIG_NET_CLS_ACT
tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
kfree(exts->actions);
exts->nr_actions = 0;
#endif
}
EXPORT_SYMBOL(tcf_exts_destroy);
int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
bool rtnl_held, struct netlink_ext_ack *extack)
{
#ifdef CONFIG_NET_CLS_ACT
{
struct tc_action *act;
size_t attr_size = 0;
if (exts->police && tb[exts->police]) {
act = tcf_action_init_1(net, tp, tb[exts->police],
rate_tlv, "police", ovr,
TCA_ACT_BIND, rtnl_held,
extack);
if (IS_ERR(act))
return PTR_ERR(act);
act->type = exts->type = TCA_OLD_COMPAT;
exts->actions[0] = act;
exts->nr_actions = 1;
} else if (exts->action && tb[exts->action]) {
int err;
err = tcf_action_init(net, tp, tb[exts->action],
rate_tlv, NULL, ovr, TCA_ACT_BIND,
exts->actions, &attr_size,
rtnl_held, extack);
if (err < 0)
return err;
exts->nr_actions = err;
}
}
#else
if ((exts->action && tb[exts->action]) ||
(exts->police && tb[exts->police])) {
NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
return -EOPNOTSUPP;
}
#endif
return 0;
}
EXPORT_SYMBOL(tcf_exts_validate);
void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
{
#ifdef CONFIG_NET_CLS_ACT
struct tcf_exts old = *dst;
*dst = *src;
tcf_exts_destroy(&old);
#endif
}
EXPORT_SYMBOL(tcf_exts_change);
#ifdef CONFIG_NET_CLS_ACT
static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
{
if (exts->nr_actions == 0)
return NULL;
else
return exts->actions[0];
}
#endif
int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
{
#ifdef CONFIG_NET_CLS_ACT
struct nlattr *nest;
if (exts->action && tcf_exts_has_actions(exts)) {
/*
* again for backward compatible mode - we want
* to work with both old and new modes of entering
* tc data even if iproute2 was newer - jhs
*/
if (exts->type != TCA_OLD_COMPAT) {
nest = nla_nest_start_noflag(skb, exts->action);
if (nest == NULL)
goto nla_put_failure;
if (tcf_action_dump(skb, exts->actions, 0, 0) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
} else if (exts->police) {
struct tc_action *act = tcf_exts_first_act(exts);
nest = nla_nest_start_noflag(skb, exts->police);
if (nest == NULL || !act)
goto nla_put_failure;
if (tcf_action_dump_old(skb, act, 0, 0) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
}
}
return 0;
nla_put_failure:
nla_nest_cancel(skb, nest);
return -1;
#else
return 0;
#endif
}
EXPORT_SYMBOL(tcf_exts_dump);
int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
{
#ifdef CONFIG_NET_CLS_ACT
struct tc_action *a = tcf_exts_first_act(exts);
if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
return -1;
#endif
return 0;
}
EXPORT_SYMBOL(tcf_exts_dump_stats);
int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
void *type_data, bool err_stop)
{
struct flow_block_cb *block_cb;
int ok_count = 0;
int err;
/* Make sure all netdevs sharing this block are offload-capable. */
if (block->nooffloaddevcnt && err_stop)
return -EOPNOTSUPP;
list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
err = block_cb->cb(type, type_data, block_cb->cb_priv);
if (err) {
if (err_stop)
return err;
} else {
ok_count++;
}
}
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_call);
int tc_setup_flow_action(struct flow_action *flow_action,
const struct tcf_exts *exts)
{
const struct tc_action *act;
int i, j, k;
if (!exts)
return 0;
j = 0;
tcf_exts_for_each_action(i, act, exts) {
struct flow_action_entry *entry;
entry = &flow_action->entries[j];
if (is_tcf_gact_ok(act)) {
entry->id = FLOW_ACTION_ACCEPT;
} else if (is_tcf_gact_shot(act)) {
entry->id = FLOW_ACTION_DROP;
} else if (is_tcf_gact_trap(act)) {
entry->id = FLOW_ACTION_TRAP;
} else if (is_tcf_gact_goto_chain(act)) {
entry->id = FLOW_ACTION_GOTO;
entry->chain_index = tcf_gact_goto_chain_index(act);
} else if (is_tcf_mirred_egress_redirect(act)) {
entry->id = FLOW_ACTION_REDIRECT;
entry->dev = tcf_mirred_dev(act);
} else if (is_tcf_mirred_egress_mirror(act)) {
entry->id = FLOW_ACTION_MIRRED;
entry->dev = tcf_mirred_dev(act);
} else if (is_tcf_vlan(act)) {
switch (tcf_vlan_action(act)) {
case TCA_VLAN_ACT_PUSH:
entry->id = FLOW_ACTION_VLAN_PUSH;
entry->vlan.vid = tcf_vlan_push_vid(act);
entry->vlan.proto = tcf_vlan_push_proto(act);
entry->vlan.prio = tcf_vlan_push_prio(act);
break;
case TCA_VLAN_ACT_POP:
entry->id = FLOW_ACTION_VLAN_POP;
break;
case TCA_VLAN_ACT_MODIFY:
entry->id = FLOW_ACTION_VLAN_MANGLE;
entry->vlan.vid = tcf_vlan_push_vid(act);
entry->vlan.proto = tcf_vlan_push_proto(act);
entry->vlan.prio = tcf_vlan_push_prio(act);
break;
default:
goto err_out;
}
} else if (is_tcf_tunnel_set(act)) {
entry->id = FLOW_ACTION_TUNNEL_ENCAP;
entry->tunnel = tcf_tunnel_info(act);
} else if (is_tcf_tunnel_release(act)) {
entry->id = FLOW_ACTION_TUNNEL_DECAP;
} else if (is_tcf_pedit(act)) {
for (k = 0; k < tcf_pedit_nkeys(act); k++) {
switch (tcf_pedit_cmd(act, k)) {
case TCA_PEDIT_KEY_EX_CMD_SET:
entry->id = FLOW_ACTION_MANGLE;
break;
case TCA_PEDIT_KEY_EX_CMD_ADD:
entry->id = FLOW_ACTION_ADD;
break;
default:
goto err_out;
}
entry->mangle.htype = tcf_pedit_htype(act, k);
entry->mangle.mask = tcf_pedit_mask(act, k);
entry->mangle.val = tcf_pedit_val(act, k);
entry->mangle.offset = tcf_pedit_offset(act, k);
entry = &flow_action->entries[++j];
}
} else if (is_tcf_csum(act)) {
entry->id = FLOW_ACTION_CSUM;
entry->csum_flags = tcf_csum_update_flags(act);
} else if (is_tcf_skbedit_mark(act)) {
entry->id = FLOW_ACTION_MARK;
entry->mark = tcf_skbedit_mark(act);
} else if (is_tcf_sample(act)) {
entry->id = FLOW_ACTION_SAMPLE;
entry->sample.psample_group =
tcf_sample_psample_group(act);
entry->sample.trunc_size = tcf_sample_trunc_size(act);
entry->sample.truncate = tcf_sample_truncate(act);
entry->sample.rate = tcf_sample_rate(act);
} else if (is_tcf_police(act)) {
entry->id = FLOW_ACTION_POLICE;
entry->police.burst = tcf_police_tcfp_burst(act);
entry->police.rate_bytes_ps =
tcf_police_rate_bytes_ps(act);
net/sched: Introduce action ct Allow sending a packet to conntrack module for connection tracking. The packet will be marked with conntrack connection's state, and any metadata such as conntrack mark and label. This state metadata can later be matched against with tc classifers, for example with the flower classifier as below. In addition to committing new connections the user can optionally specific a zone to track within, set a mark/label and configure nat with an address range and port range. Usage is as follows: $ tc qdisc add dev ens1f0_0 ingress $ tc qdisc add dev ens1f0_1 ingress $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 0 proto ip \ flower ip_proto tcp ct_state -trk \ action ct zone 2 pipe \ action goto chain 2 $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 2 proto ip \ flower ct_state +trk+new \ action ct zone 2 commit mark 0xbb nat src addr 5.5.5.7 pipe \ action mirred egress redirect dev ens1f0_1 $ tc filter add dev ens1f0_0 ingress \ prio 1 chain 2 proto ip \ flower ct_zone 2 ct_mark 0xbb ct_state +trk+est \ action ct nat pipe \ action mirred egress redirect dev ens1f0_1 $ tc filter add dev ens1f0_1 ingress \ prio 1 chain 0 proto ip \ flower ip_proto tcp ct_state -trk \ action ct zone 2 pipe \ action goto chain 1 $ tc filter add dev ens1f0_1 ingress \ prio 1 chain 1 proto ip \ flower ct_zone 2 ct_mark 0xbb ct_state +trk+est \ action ct nat pipe \ action mirred egress redirect dev ens1f0_0 Signed-off-by: Paul Blakey <paulb@mellanox.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Yossi Kuperman <yossiku@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Changelog: V5->V6: Added CONFIG_NF_DEFRAG_IPV6 in handle fragments ipv6 case V4->V5: Reordered nf_conntrack_put() in tcf_ct_skb_nfct_cached() V3->V4: Added strict_start_type for act_ct policy V2->V3: Fixed david's comments: Removed extra newline after rcu in tcf_ct_params , and indent of break in act_ct.c V1->V2: Fixed parsing of ranges TCA_CT_NAT_IPV6_MAX as 'else' case overwritten ipv4 max Refactored NAT_PORT_MIN_MAX range handling as well Added ipv4/ipv6 defragmentation Removed extra skb pull push of nw offset in exectute nat Refactored tcf_ct_skb_network_trim after pull Removed TCA_ACT_CT define Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09 09:30:48 +02:00
} else if (is_tcf_ct(act)) {
entry->id = FLOW_ACTION_CT;
entry->ct.action = tcf_ct_action(act);
entry->ct.zone = tcf_ct_zone(act);
} else {
goto err_out;
}
if (!is_tcf_pedit(act))
j++;
}
return 0;
err_out:
return -EOPNOTSUPP;
}
EXPORT_SYMBOL(tc_setup_flow_action);
unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
{
unsigned int num_acts = 0;
struct tc_action *act;
int i;
tcf_exts_for_each_action(i, act, exts) {
if (is_tcf_pedit(act))
num_acts += tcf_pedit_nkeys(act);
else
num_acts++;
}
return num_acts;
}
EXPORT_SYMBOL(tcf_exts_num_actions);
static __net_init int tcf_net_init(struct net *net)
{
struct tcf_net *tn = net_generic(net, tcf_net_id);
spin_lock_init(&tn->idr_lock);
idr_init(&tn->idr);
return 0;
}
static void __net_exit tcf_net_exit(struct net *net)
{
struct tcf_net *tn = net_generic(net, tcf_net_id);
idr_destroy(&tn->idr);
}
static struct pernet_operations tcf_net_ops = {
.init = tcf_net_init,
.exit = tcf_net_exit,
.id = &tcf_net_id,
.size = sizeof(struct tcf_net),
};
static int __init tc_filter_init(void)
{
int err;
tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
if (!tc_filter_wq)
return -ENOMEM;
err = register_pernet_subsys(&tcf_net_ops);
if (err)
goto err_register_pernet_subsys;
err = rhashtable_init(&indr_setup_block_ht,
&tc_indr_setup_block_ht_params);
if (err)
goto err_rhash_setup_block_ht;
rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
RTNL_FLAG_DOIT_UNLOCKED);
rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
RTNL_FLAG_DOIT_UNLOCKED);
rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
tc_dump_chain, 0);
return 0;
err_rhash_setup_block_ht:
unregister_pernet_subsys(&tcf_net_ops);
err_register_pernet_subsys:
destroy_workqueue(tc_filter_wq);
return err;
}
subsys_initcall(tc_filter_init);