Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Alexei Starovoitov says:

====================
pull-request: bpf 2018-12-15

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) fix liveness propagation of callee saved registers, from Jakub.

2) fix overflow in bpf_jit_limit knob, from Daniel.

3) bpf_flow_dissector api fix, from Stanislav.

4) bpf_perf_event api fix on powerpc, from Sandipan.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2018-12-15 10:58:32 -08:00
commit 10589a568f
10 changed files with 109 additions and 39 deletions

View File

@ -26,6 +26,8 @@
#include <asm/ptrace.h>
#include <asm/reg.h>
#define perf_arch_bpf_user_pt_regs(regs) &regs->user_regs
/*
* Overload regs->result to specify whether we should use the MSR (result
* is zero) or the SIAR (result is non zero).

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@ -1,7 +1,6 @@
# UAPI Header export list
include include/uapi/asm-generic/Kbuild.asm
generic-y += bpf_perf_event.h
generic-y += param.h
generic-y += poll.h
generic-y += resource.h

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@ -0,0 +1,9 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _UAPI__ASM_BPF_PERF_EVENT_H__
#define _UAPI__ASM_BPF_PERF_EVENT_H__
#include <asm/ptrace.h>
typedef struct user_pt_regs bpf_user_pt_regs_t;
#endif /* _UAPI__ASM_BPF_PERF_EVENT_H__ */

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@ -861,7 +861,7 @@ bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
extern int bpf_jit_enable;
extern int bpf_jit_harden;
extern int bpf_jit_kallsyms;
extern int bpf_jit_limit;
extern long bpf_jit_limit;
typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);

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@ -365,13 +365,11 @@ void bpf_prog_kallsyms_del_all(struct bpf_prog *fp)
}
#ifdef CONFIG_BPF_JIT
# define BPF_JIT_LIMIT_DEFAULT (PAGE_SIZE * 40000)
/* All BPF JIT sysctl knobs here. */
int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON);
int bpf_jit_harden __read_mostly;
int bpf_jit_kallsyms __read_mostly;
int bpf_jit_limit __read_mostly = BPF_JIT_LIMIT_DEFAULT;
long bpf_jit_limit __read_mostly;
static __always_inline void
bpf_get_prog_addr_region(const struct bpf_prog *prog,
@ -580,16 +578,27 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
static atomic_long_t bpf_jit_current;
/* Can be overridden by an arch's JIT compiler if it has a custom,
* dedicated BPF backend memory area, or if neither of the two
* below apply.
*/
u64 __weak bpf_jit_alloc_exec_limit(void)
{
#if defined(MODULES_VADDR)
return MODULES_END - MODULES_VADDR;
#else
return VMALLOC_END - VMALLOC_START;
#endif
}
static int __init bpf_jit_charge_init(void)
{
/* Only used as heuristic here to derive limit. */
bpf_jit_limit = min_t(u64, round_up((MODULES_END - MODULES_VADDR) >> 2,
PAGE_SIZE), INT_MAX);
bpf_jit_limit = min_t(u64, round_up(bpf_jit_alloc_exec_limit() >> 2,
PAGE_SIZE), LONG_MAX);
return 0;
}
pure_initcall(bpf_jit_charge_init);
#endif
static int bpf_jit_charge_modmem(u32 pages)
{

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@ -5102,9 +5102,16 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
}
new_sl->next = env->explored_states[insn_idx];
env->explored_states[insn_idx] = new_sl;
/* connect new state to parentage chain */
for (i = 0; i < BPF_REG_FP; i++)
cur_regs(env)[i].parent = &new->frame[new->curframe]->regs[i];
/* connect new state to parentage chain. Current frame needs all
* registers connected. Only r6 - r9 of the callers are alive (pushed
* to the stack implicitly by JITs) so in callers' frames connect just
* r6 - r9 as an optimization. Callers will have r1 - r5 connected to
* the state of the call instruction (with WRITTEN set), and r0 comes
* from callee with its full parentage chain, anyway.
*/
for (j = 0; j <= cur->curframe; j++)
for (i = j < cur->curframe ? BPF_REG_6 : 0; i < BPF_REG_FP; i++)
cur->frame[j]->regs[i].parent = &new->frame[j]->regs[i];
/* clear write marks in current state: the writes we did are not writes
* our child did, so they don't screen off its reads from us.
* (There are no read marks in current state, because reads always mark

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@ -783,6 +783,7 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
/* Pass parameters to the BPF program */
cb->qdisc_cb.flow_keys = &flow_keys;
flow_keys.nhoff = nhoff;
flow_keys.thoff = nhoff;
bpf_compute_data_pointers((struct sk_buff *)skb);
result = BPF_PROG_RUN(attached, skb);
@ -790,9 +791,12 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
/* Restore state */
memcpy(cb, &cb_saved, sizeof(cb_saved));
flow_keys.nhoff = clamp_t(u16, flow_keys.nhoff, 0, skb->len);
flow_keys.thoff = clamp_t(u16, flow_keys.thoff,
flow_keys.nhoff, skb->len);
__skb_flow_bpf_to_target(&flow_keys, flow_dissector,
target_container);
key_control->thoff = min_t(u16, key_control->thoff, skb->len);
rcu_read_unlock();
return result == BPF_OK;
}

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@ -28,6 +28,8 @@ static int two __maybe_unused = 2;
static int min_sndbuf = SOCK_MIN_SNDBUF;
static int min_rcvbuf = SOCK_MIN_RCVBUF;
static int max_skb_frags = MAX_SKB_FRAGS;
static long long_one __maybe_unused = 1;
static long long_max __maybe_unused = LONG_MAX;
static int net_msg_warn; /* Unused, but still a sysctl */
@ -289,6 +291,17 @@ proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
}
static int
proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
}
#endif
static struct ctl_table net_core_table[] = {
@ -398,10 +411,11 @@ static struct ctl_table net_core_table[] = {
{
.procname = "bpf_jit_limit",
.data = &bpf_jit_limit,
.maxlen = sizeof(int),
.maxlen = sizeof(long),
.mode = 0600,
.proc_handler = proc_dointvec_minmax_bpf_restricted,
.extra1 = &one,
.proc_handler = proc_dolongvec_minmax_bpf_restricted,
.extra1 = &long_one,
.extra2 = &long_max,
},
#endif
{

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@ -70,18 +70,18 @@ static __always_inline void *bpf_flow_dissect_get_header(struct __sk_buff *skb,
{
void *data_end = (void *)(long)skb->data_end;
void *data = (void *)(long)skb->data;
__u16 nhoff = skb->flow_keys->nhoff;
__u16 thoff = skb->flow_keys->thoff;
__u8 *hdr;
/* Verifies this variable offset does not overflow */
if (nhoff > (USHRT_MAX - hdr_size))
if (thoff > (USHRT_MAX - hdr_size))
return NULL;
hdr = data + nhoff;
hdr = data + thoff;
if (hdr + hdr_size <= data_end)
return hdr;
if (bpf_skb_load_bytes(skb, nhoff, buffer, hdr_size))
if (bpf_skb_load_bytes(skb, thoff, buffer, hdr_size))
return NULL;
return buffer;
@ -158,13 +158,13 @@ static __always_inline int parse_ip_proto(struct __sk_buff *skb, __u8 proto)
/* Only inspect standard GRE packets with version 0 */
return BPF_OK;
keys->nhoff += sizeof(*gre); /* Step over GRE Flags and Proto */
keys->thoff += sizeof(*gre); /* Step over GRE Flags and Proto */
if (GRE_IS_CSUM(gre->flags))
keys->nhoff += 4; /* Step over chksum and Padding */
keys->thoff += 4; /* Step over chksum and Padding */
if (GRE_IS_KEY(gre->flags))
keys->nhoff += 4; /* Step over key */
keys->thoff += 4; /* Step over key */
if (GRE_IS_SEQ(gre->flags))
keys->nhoff += 4; /* Step over sequence number */
keys->thoff += 4; /* Step over sequence number */
keys->is_encap = true;
@ -174,7 +174,7 @@ static __always_inline int parse_ip_proto(struct __sk_buff *skb, __u8 proto)
if (!eth)
return BPF_DROP;
keys->nhoff += sizeof(*eth);
keys->thoff += sizeof(*eth);
return parse_eth_proto(skb, eth->h_proto);
} else {
@ -191,7 +191,6 @@ static __always_inline int parse_ip_proto(struct __sk_buff *skb, __u8 proto)
if ((__u8 *)tcp + (tcp->doff << 2) > data_end)
return BPF_DROP;
keys->thoff = keys->nhoff;
keys->sport = tcp->source;
keys->dport = tcp->dest;
return BPF_OK;
@ -201,7 +200,6 @@ static __always_inline int parse_ip_proto(struct __sk_buff *skb, __u8 proto)
if (!udp)
return BPF_DROP;
keys->thoff = keys->nhoff;
keys->sport = udp->source;
keys->dport = udp->dest;
return BPF_OK;
@ -252,8 +250,8 @@ PROG(IP)(struct __sk_buff *skb)
keys->ipv4_src = iph->saddr;
keys->ipv4_dst = iph->daddr;
keys->nhoff += iph->ihl << 2;
if (data + keys->nhoff > data_end)
keys->thoff += iph->ihl << 2;
if (data + keys->thoff > data_end)
return BPF_DROP;
if (iph->frag_off & bpf_htons(IP_MF | IP_OFFSET)) {
@ -285,7 +283,7 @@ PROG(IPV6)(struct __sk_buff *skb)
keys->addr_proto = ETH_P_IPV6;
memcpy(&keys->ipv6_src, &ip6h->saddr, 2*sizeof(ip6h->saddr));
keys->nhoff += sizeof(struct ipv6hdr);
keys->thoff += sizeof(struct ipv6hdr);
return parse_ipv6_proto(skb, ip6h->nexthdr);
}
@ -301,7 +299,7 @@ PROG(IPV6OP)(struct __sk_buff *skb)
/* hlen is in 8-octets and does not include the first 8 bytes
* of the header
*/
skb->flow_keys->nhoff += (1 + ip6h->hdrlen) << 3;
skb->flow_keys->thoff += (1 + ip6h->hdrlen) << 3;
return parse_ipv6_proto(skb, ip6h->nexthdr);
}
@ -315,7 +313,7 @@ PROG(IPV6FR)(struct __sk_buff *skb)
if (!fragh)
return BPF_DROP;
keys->nhoff += sizeof(*fragh);
keys->thoff += sizeof(*fragh);
keys->is_frag = true;
if (!(fragh->frag_off & bpf_htons(IP6_OFFSET)))
keys->is_first_frag = true;
@ -341,7 +339,7 @@ PROG(VLAN)(struct __sk_buff *skb)
__be16 proto;
/* Peek back to see if single or double-tagging */
if (bpf_skb_load_bytes(skb, keys->nhoff - sizeof(proto), &proto,
if (bpf_skb_load_bytes(skb, keys->thoff - sizeof(proto), &proto,
sizeof(proto)))
return BPF_DROP;
@ -354,14 +352,14 @@ PROG(VLAN)(struct __sk_buff *skb)
if (vlan->h_vlan_encapsulated_proto != bpf_htons(ETH_P_8021Q))
return BPF_DROP;
keys->nhoff += sizeof(*vlan);
keys->thoff += sizeof(*vlan);
}
vlan = bpf_flow_dissect_get_header(skb, sizeof(*vlan), &_vlan);
if (!vlan)
return BPF_DROP;
keys->nhoff += sizeof(*vlan);
keys->thoff += sizeof(*vlan);
/* Only allow 8021AD + 8021Q double tagging and no triple tagging.*/
if (vlan->h_vlan_encapsulated_proto == bpf_htons(ETH_P_8021AD) ||
vlan->h_vlan_encapsulated_proto == bpf_htons(ETH_P_8021Q))

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@ -13915,6 +13915,34 @@ static struct bpf_test tests[] = {
.result_unpriv = REJECT,
.result = ACCEPT,
},
{
"calls: cross frame pruning",
.insns = {
/* r8 = !!random();
* call pruner()
* if (r8)
* do something bad;
*/
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_prandom_u32),
BPF_MOV64_IMM(BPF_REG_8, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_MOV64_IMM(BPF_REG_8, 1),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_8),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 4),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_8, 1, 1),
BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_1, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
.errstr_unpriv = "function calls to other bpf functions are allowed for root only",
.result_unpriv = REJECT,
.errstr = "!read_ok",
.result = REJECT,
},
};
static int probe_filter_length(const struct bpf_insn *fp)
@ -13940,7 +13968,7 @@ static int create_map(uint32_t type, uint32_t size_key,
return fd;
}
static int create_prog_dummy1(enum bpf_map_type prog_type)
static int create_prog_dummy1(enum bpf_prog_type prog_type)
{
struct bpf_insn prog[] = {
BPF_MOV64_IMM(BPF_REG_0, 42),
@ -13951,7 +13979,7 @@ static int create_prog_dummy1(enum bpf_map_type prog_type)
ARRAY_SIZE(prog), "GPL", 0, NULL, 0);
}
static int create_prog_dummy2(enum bpf_map_type prog_type, int mfd, int idx)
static int create_prog_dummy2(enum bpf_prog_type prog_type, int mfd, int idx)
{
struct bpf_insn prog[] = {
BPF_MOV64_IMM(BPF_REG_3, idx),
@ -13966,7 +13994,7 @@ static int create_prog_dummy2(enum bpf_map_type prog_type, int mfd, int idx)
ARRAY_SIZE(prog), "GPL", 0, NULL, 0);
}
static int create_prog_array(enum bpf_map_type prog_type, uint32_t max_elem,
static int create_prog_array(enum bpf_prog_type prog_type, uint32_t max_elem,
int p1key)
{
int p2key = 1;
@ -14037,7 +14065,7 @@ static int create_cgroup_storage(bool percpu)
static char bpf_vlog[UINT_MAX >> 8];
static void do_test_fixup(struct bpf_test *test, enum bpf_map_type prog_type,
static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
struct bpf_insn *prog, int *map_fds)
{
int *fixup_map_hash_8b = test->fixup_map_hash_8b;
@ -14166,7 +14194,7 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_map_type prog_type,
do {
prog[*fixup_map_stacktrace].imm = map_fds[12];
fixup_map_stacktrace++;
} while (fixup_map_stacktrace);
} while (*fixup_map_stacktrace);
}
}