Userspace should not abuse the kernel to store large amounts of data,
reject requests larger than the private area can accommodate.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
add a 32 byte scratch area in the helper struct instead of relying
on variable sized helpers plus compile-time asserts to let us know
if 32 bytes aren't enough anymore.
Not having variable sized helpers will later allow to add BUILD_BUG_ON
for the total size of conntrack extensions -- the helper extension is
the only one that doesn't have a fixed size.
The (useless!) NF_CT_HELPER_BUILD_BUG_ON(0); are added so that in case
someone adds a new helper and copy-pastes from one that doesn't store
private data at least some indication that this macro should be used
somehow is there...
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
By default the kernel emits all ctnetlink events for a connection.
This allows to select the types of events to generate.
This can be used to e.g. only send DESTROY events but no NEW/UPDATE ones
and will work even if sysctl net.netfilter.nf_conntrack_events is set to 0.
This was already possible via iptables' CT target, but the nft version has
the advantage that it can also be used with already-established conntracks.
The added nf_ct_is_template() check isn't a bug fix as we only support
mark and labels (and unlike ecache the conntrack core doesn't copy those).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This function is now obsolete and always returns false.
This change has no effect on generated code.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
resurrect an old patch from Pablo Neira to remove the untracked objects.
Currently, there are four possible states of an skb wrt. conntrack.
1. No conntrack attached, ct is NULL.
2. Normal (kmem cache allocated) ct attached.
3. a template (kmalloc'd), not in any hash tables at any point in time
4. the 'untracked' conntrack, a percpu nf_conn object, tagged via
IPS_UNTRACKED_BIT in ct->status.
Untracked is supposed to be identical to case 1. It exists only
so users can check
-m conntrack --ctstate UNTRACKED vs.
-m conntrack --ctstate INVALID
e.g. attempts to set connmark on INVALID or UNTRACKED conntracks is
supposed to be a no-op.
Thus currently we need to check
ct == NULL || nf_ct_is_untracked(ct)
in a lot of places in order to avoid altering untracked objects.
The other consequence of the percpu untracked object is that all
-j NOTRACK (and, later, kfree_skb of such skbs) result in an atomic op
(inc/dec the untracked conntracks refcount).
This adds a new kernel-private ctinfo state, IP_CT_UNTRACKED, to
make the distinction instead.
The (few) places that care about packet invalid (ct is NULL) vs.
packet untracked now need to test ct == NULL vs. ctinfo == IP_CT_UNTRACKED,
but all other places can omit the nf_ct_is_untracked() check.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1. Remove single !events condition check to deliver the missed event
even though there is no new event happened.
Consider this case:
1) nf_ct_deliver_cached_events is invoked at the first time, the
event is failed to deliver, then the missed is set.
2) nf_ct_deliver_cached_events is invoked again, but there is no
any new event happened.
The missed event is lost really.
It would try to send the missed event again after remove this check.
And it is ok if there is no missed event because the latter check
!((events | missed) & e->ctmask) could avoid it.
2. Correct the return value check of notify->fcn.
When send the event successfully, it returns 0, not postive value.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The __nf_nat_alloc_null_binding invokes nf_nat_setup_info which may
return NF_DROP when memory is exhausted, so convert NF_DROP to -ENOMEM
to make ctnetlink happy. Or ctnetlink_setup_nat treats it as a success
when one error NF_DROP happens actully.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Simon Horman says:
====================
Second Round of IPVS Updates for v4.12
please consider these clean-ups and enhancements to IPVS for v4.12.
* Removal unused variable
* Use kzalloc where appropriate
* More efficient detection of presence of NAT extension
====================
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
net/netfilter/ipvs/ip_vs_ftp.c
There are no in-tree callers.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The protonet pointer will unconditionally be rewritten, so just do the
needed assignment first.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
__nf_nat_decode_session is called from nf_nat_decode_session as decodefn.
before calling decodefn, it already set rcu_read_lock. so rcu_read_lock in
__nf_nat_decode_session can be removed.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Remove & from function pointers to conform to the style found elsewhere
in the file. Done using the following semantic patch
// <smpl>
@r@
identifier f;
@@
f(...) { ... }
@@
identifier r.f;
@@
- &f
+ f
// </smpl>
Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch replace list_entry with list_prev_entry as it makes the
code more clear to read.
Signed-off-by: simran singhal <singhalsimran0@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For string without format specifiers, use seq_puts(). For
seq_printf("\n"), use seq_putc('\n').
Signed-off-by: simran singhal <singhalsimran0@gmail.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The following Coccinelle script was used to detect this:
@r@
expression x;
void* e;
type T;
identifier f;
@@
(
*((T *)e)
|
((T *)x)[...]
|
((T*)x)->f
|
- (T*)
e
)
Unnecessary parantheses are also remove.
Signed-off-by: simran singhal <singhalsimran0@gmail.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add and use nfnl_msg_type() function to replace opencoded nfnetlink
message type. I suggested this change, Arushi Singhal made an initial
patch to address this but was missing several spots.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The expect check function __nf_ct_expect_check() asks the master_help is
necessary. So it is unnecessary to go ahead in ctnetlink_alloc_expect
when there is no help.
Actually the commit bc01befdcf ("netfilter: ctnetlink: add support for
user-space expectation helpers") permits ctnetlink create one expect
even though there is no master help. But the latter commit 3d058d7bc2
("netfilter: rework user-space expectation helper support") disables it
again.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
successful insert into the bysource hash sets IPS_SRC_NAT_DONE status bit
so we can check that instead of presence of nat extension which requires
extra deref.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_nat_mangle_{udp,tcp}_packet() returns int. However, it is used as
bool type in many spots. Fix this by consistently handle this return
value as a boolean.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When remove one expect, it needs three statements. And there are
multiple duplicated codes in current code. So add one common function
nf_ct_remove_expect to consolidate this.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Because the type of expecting, the member of nf_conn_help, is u8, it
would overflow after reach U8_MAX(255). So it doesn't work when we
configure the max_expected exceeds 255 with expect policy.
Now add the check for max_expected. Return the -EINVAL when it exceeds
the limit.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Mostly simple cases of overlapping changes (adding code nearby,
a function whose name changes, for example).
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch uses the following coccinelle script to remove
a variable that was simply used to store the return
value of a function call before returning it:
@@
identifier len,f;
@@
-int len;
... when != len
when strict
-len =
+return
f(...);
-return len;
Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Replace kzalloc with kcalloc. As kcalloc is preferred for allocating an
array instead of kzalloc. This patch fixes the checkpatch issue.
Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Check for the NAT status bits, they are set once conntrack needs NAT in source or
reply direction, this is slightly faster than nfct_nat() as that has to check the
extension area.
Signed-off-by: Florian Westphal <fw@strlen.de>
We must call security_release_secctx to free the memory returned by
security_secid_to_secctx, otherwise memory may be leaked forever.
Fixes: ef493bd930 ("netfilter: nfnetlink_queue: add security context information")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If one cpu is doing nf_ct_extend_unregister while another cpu is doing
__nf_ct_ext_add_length, then we may hit BUG_ON(t == NULL). Moreover,
there's no synchronize_rcu invocation after set nf_ct_ext_types[id] to
NULL, so it's possible that we may access invalid pointer.
But actually, most of the ct extends are built-in, so the problem listed
above will not happen. However, there are two exceptions: NF_CT_EXT_NAT
and NF_CT_EXT_SYNPROXY.
For _EXT_NAT, the panic will not happen, since adding the nat extend and
unregistering the nat extend are located in the same file(nf_nat_core.c),
this means that after the nat module is removed, we cannot add the nat
extend too.
For _EXT_SYNPROXY, synproxy extend may be added by init_conntrack, while
synproxy extend unregister will be done by synproxy_core_exit. So after
nf_synproxy_core.ko is removed, we may still try to add the synproxy
extend, then kernel panic may happen.
I know it's very hard to reproduce this issue, but I can play a tricky
game to make it happen very easily :)
Step 1. Enable SYNPROXY for tcp dport 1234 at FORWARD hook:
# iptables -I FORWARD -p tcp --dport 1234 -j SYNPROXY
Step 2. Queue the syn packet to the userspace at raw table OUTPUT hook.
Also note, in the userspace we only add a 20s' delay, then
reinject the syn packet to the kernel:
# iptables -t raw -I OUTPUT -p tcp --syn -j NFQUEUE --queue-num 1
Step 3. Using "nc 2.2.2.2 1234" to connect the server.
Step 4. Now remove the nf_synproxy_core.ko quickly:
# iptables -F FORWARD
# rmmod ipt_SYNPROXY
# rmmod nf_synproxy_core
Step 5. After 20s' delay, the syn packet is reinjected to the kernel.
Now you will see the panic like this:
kernel BUG at net/netfilter/nf_conntrack_extend.c:91!
Call Trace:
? __nf_ct_ext_add_length+0x53/0x3c0 [nf_conntrack]
init_conntrack+0x12b/0x600 [nf_conntrack]
nf_conntrack_in+0x4cc/0x580 [nf_conntrack]
ipv4_conntrack_local+0x48/0x50 [nf_conntrack_ipv4]
nf_reinject+0x104/0x270
nfqnl_recv_verdict+0x3e1/0x5f9 [nfnetlink_queue]
? nfqnl_recv_verdict+0x5/0x5f9 [nfnetlink_queue]
? nla_parse+0xa0/0x100
nfnetlink_rcv_msg+0x175/0x6a9 [nfnetlink]
[...]
One possible solution is to make NF_CT_EXT_SYNPROXY extend built-in, i.e.
introduce nf_conntrack_synproxy.c and only do ct extend register and
unregister in it, similar to nf_conntrack_timeout.c.
But having such a obscure restriction of nf_ct_extend_unregister is not a
good idea, so we should invoke synchronize_rcu after set nf_ct_ext_types
to NULL, and check the NULL pointer when do __nf_ct_ext_add_length. Then
it will be easier if we add new ct extend in the future.
Last, we use kfree_rcu to free nf_ct_ext, so rcu_barrier() is unnecessary
anymore, remove it too.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The nf_ct_helper_hash table is protected by nf_ct_helper_mutex, while
nfct_helper operation is protected by nfnl_lock(NFNL_SUBSYS_CTHELPER).
So it's possible that one CPU is walking the nf_ct_helper_hash for
cthelper add/get/del, another cpu is doing nf_conntrack_helpers_unregister
at the same time. This is dangrous, and may cause use after free error.
Note, delete operation will flush all cthelpers added via nfnetlink, so
using rcu to do protect is not easy.
Now introduce a dummy list to record all the cthelpers added via
nfnetlink, then we can walk the dummy list instead of walking the
nf_ct_helper_hash. Also, keep nfnl_cthelper_dump_table unchanged, it
may be invoked without nfnl_lock(NFNL_SUBSYS_CTHELPER) held.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Otherwise, another CPU may access the invalid pointer. For example:
CPU0 CPU1
- rcu_read_lock();
- pfunc = _hook_;
_hook_ = NULL; -
mod unload -
- pfunc(); // invalid, panic
- rcu_read_unlock();
So we must call synchronize_rcu() to wait the rcu reader to finish.
Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.
Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/ethernet/broadcom/genet/bcmmii.c
drivers/net/hyperv/netvsc.c
kernel/bpf/hashtab.c
Almost entirely overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
We have memory leaks of nf_conntrack_helper & expect_policy.
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We only allow runtime updates of expectation policies for timeout and
maximum number of expectations, otherwise reject the update.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Liping Zhang <zlpnobody@gmail.com>
The helper->expect_class_max must be set to the total number of
expect_policy minus 1, since we will use the statement "if (class >
helper->expect_class_max)" to validate the CTA_EXPECT_CLASS attr in
ctnetlink_alloc_expect.
So for compatibility, set the helper->expect_class_max to the
NFCTH_POLICY_SET_NUM attr's value minus 1.
Also: it's invalid when the NFCTH_POLICY_SET_NUM attr's value is zero.
1. this will result "expect_policy = kzalloc(0, GFP_KERNEL);";
2. we cannot set the helper->expect_class_max to a proper value.
So if nla_get_be32(tb[NFCTH_POLICY_SET_NUM]) is zero, report -EINVAL to
the userspace.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
refcount_t type and corresponding API (see include/linux/refcount.h)
should be used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
At most it is used for debugging purpose, but I don't think
it is even useful for debugging, just remove it.
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
We should jump to invoke __nft_ct_set_destroy() instead of just
return error.
Fixes: edee4f1e92 ("netfilter: nft_ct: add zone id set support")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Karel Rericha reported that in his test case, ICMP packets going through
boxes had normally about 5ms latency. But when running nft, actually
listing the sets with interval flags, latency would go up to 30-100ms.
This was observed when router throughput is from 600Mbps to 2Gbps.
This is because we use a single global spinlock to protect the whole
rbtree sets, so "dumping sets" will race with the "key lookup" inevitably.
But actually they are all _readers_, so it's ok to convert the spinlock
to rwlock to avoid competition between them. Also use per-set rwlock since
each set is independent.
Reported-by: Karel Rericha <karel@unitednetworks.cz>
Tested-by: Karel Rericha <karel@unitednetworks.cz>
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The limit token is independent between each rules, so there's no
need to use a global spinlock.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
also mark init_conntrack noinline, in most cases resolve_normal_ct will
find an existing conntrack entry.
text data bss dec hex filename
16735 5707 176 22618 585a net/netfilter/nf_conntrack_core.o
16687 5707 176 22570 582a net/netfilter/nf_conntrack_core.o
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This reverts commit 1f48ff6c53.
This patch is not required anymore now that we keep a dummy list of
set elements in the bitmap set implementation, so revert this before
we forget this code has no clients.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of the actual interface index or name, set destination register
to just 1 or 0 depending on whether the lookup succeeded or not if
NFTA_FIB_F_PRESENT was set in userspace.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
this allows to assign connection tracking helpers to
connections via nft objref infrastructure.
The idea is to first specifiy a helper object:
table ip filter {
ct helper some-name {
type "ftp"
protocol tcp
l3proto ip
}
}
and then assign it via
nft add ... ct helper set "some-name"
helper assignment works for new conntracks only as we cannot expand the
conntrack extension area once it has been committed to the main conntrack
table.
ipv4 and ipv6 protocols are tracked stored separately so
we can also handle families that observe both ipv4 and ipv6 traffic.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
this is needed by the upcoming ct helper object type --
we'd like to be able use the table family (ip, ip6, inet) to figure
out which helper has to be requested.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Element comments may come without any prior set flag, so we have to keep
a list of dummy struct nft_set_ext to keep this information around. This
is only useful for set dumps to userspace. From the packet path, this
set type relies on the bitmap representation. This patch simplifies the
logic since we don't need to allocate the dummy nft_set_ext structure
anymore on the fly at the cost of increasing memory consumption because
of the list of dummy struct nft_set_ext.
Fixes: 665153ff57 ("netfilter: nf_tables: add bitmap set type")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since the nfct and nfctinfo have been combined, the nf_conn structure
must be at least 8 bytes aligned, as the 3 LSB bits are used for the
nfctinfo. But there's a fake nf_conn structure to denote untracked
connections, which is created by a PER_CPU construct. This does not
guarantee that it will be 8 bytes aligned and can break the logic in
determining the correct nfctinfo.
I triggered this on a 32bit machine with the following error:
BUG: unable to handle kernel NULL pointer dereference at 00000af4
IP: nf_ct_deliver_cached_events+0x1b/0xfb
*pdpt = 0000000031962001 *pde = 0000000000000000
Oops: 0000 [#1] SMP
[Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables ipv6 crc_ccitt ppdev r8169 parport_pc parport
OK ]
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.10.0-test+ #75
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
task: c126ec00 task.stack: c1258000
EIP: nf_ct_deliver_cached_events+0x1b/0xfb
EFLAGS: 00010202 CPU: 0
EAX: 0021cd01 EBX: 00000000 ECX: 27b0c767 EDX: 32bcb17a
ESI: f34135c0 EDI: f34135c0 EBP: f2debd60 ESP: f2debd3c
DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
CR0: 80050033 CR2: 00000af4 CR3: 309a0440 CR4: 001406f0
Call Trace:
<SOFTIRQ>
? ipv6_skip_exthdr+0xac/0xcb
ipv6_confirm+0x10c/0x119 [nf_conntrack_ipv6]
nf_hook_slow+0x22/0xc7
nf_hook+0x9a/0xad [ipv6]
? ip6t_do_table+0x356/0x379 [ip6_tables]
? ip6_fragment+0x9e9/0x9e9 [ipv6]
ip6_output+0xee/0x107 [ipv6]
? ip6_fragment+0x9e9/0x9e9 [ipv6]
dst_output+0x36/0x4d [ipv6]
NF_HOOK.constprop.37+0xb2/0xba [ipv6]
? icmp6_dst_alloc+0x2c/0xfd [ipv6]
? local_bh_enable+0x14/0x14 [ipv6]
mld_sendpack+0x1c5/0x281 [ipv6]
? mark_held_locks+0x40/0x5c
mld_ifc_timer_expire+0x1f6/0x21e [ipv6]
call_timer_fn+0x135/0x283
? detach_if_pending+0x55/0x55
? mld_dad_timer_expire+0x3e/0x3e [ipv6]
__run_timers+0x111/0x14b
? mld_dad_timer_expire+0x3e/0x3e [ipv6]
run_timer_softirq+0x1c/0x36
__do_softirq+0x185/0x37c
? test_ti_thread_flag.constprop.19+0xd/0xd
do_softirq_own_stack+0x22/0x28
</SOFTIRQ>
irq_exit+0x5a/0xa4
smp_apic_timer_interrupt+0x2a/0x34
apic_timer_interrupt+0x37/0x3c
By using DEFINE/DECLARE_PER_CPU_ALIGNED we can enforce at least 8 byte
alignment as all cache line sizes are at least 8 bytes or more.
Fixes: a9e419dc7b ("netfilter: merge ctinfo into nfct pointer storage area")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, there are two different methods to store an u16 integer to
the u32 data register. For example:
u32 *dest = ®s->data[priv->dreg];
1. *dest = 0; *(u16 *) dest = val_u16;
2. *dest = val_u16;
For method 1, the u16 value will be stored like this, either in
big-endian or little-endian system:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| Value | 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+
For method 2, in little-endian system, the u16 value will be the same
as listed above. But in big-endian system, the u16 value will be stored
like this:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+
So later we use "memcmp(®s->data[priv->sreg], data, 2);" to do
compare in nft_cmp, nft_lookup expr ..., method 2 will get the wrong
result in big-endian system, as 0~15 bits will always be zero.
For the similar reason, when loading an u16 value from the u32 data
register, we should use "*(u16 *) sreg;" instead of "(u16)*sreg;",
the 2nd method will get the wrong value in the big-endian system.
So introduce some wrapper functions to store/load an u8 or u16
integer to/from the u32 data register, and use them in the right
place.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently we just assume the element key as a u32 integer, regardless of
the set key length.
This is incorrect, for example, the tcp port number is only 16 bits.
So when we use the nft_payload expr to get the tcp dport and store
it to dreg, the dport will be stored at 0~15 bits, and 16~31 bits
will be padded with zero.
So the reg->data[dreg] will be looked like as below:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| tcp dport | 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+
But for these big-endian systems, if we treate this register as a u32
integer, the element key will be larger than 65535, so the following
lookup in bitmap set will cause out of bound access.
Another issue is that if we add element with comments in bitmap
set(although the comments will be ignored eventually), the element will
vanish strangely. Because we treate the element key as a u32 integer, so
the comments will become the part of the element key, then the element
key will also be larger than 65535 and out of bound access will happen:
# nft add element t s { 1 comment test }
Since set->klen is 1 or 2, it's fine to treate the element key as a u8 or
u16 integer.
Fixes: 665153ff57 ("netfilter: nf_tables: add bitmap set type")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Florian Westphal
Gao Feng
Pablo Neira Ayuso
Aaron Conole
Taehee Yoo
Arushi Singhal
simran singhal
David S. Miller
Varsha Rao
Liping Zhang
Jeffy Chen
Reshetova, Elena
Cong Wang
Phil Sutter
Steven Rostedt (VMware)