diff options
author | Alexei Starovoitov <ast@plumgrid.com> | 2015-10-07 20:55:41 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-10-11 14:40:05 +0300 |
commit | ff936a04e5f28b7e0455be0e7fa91334f89e4b44 (patch) | |
tree | f23b1f44945600ce2631560eb1f93364606b62b6 /kernel/bpf | |
parent | d49ae37c613f7cc1f4c1fd6ef073d60c32e000dd (diff) | |
download | linux-ff936a04e5f28b7e0455be0e7fa91334f89e4b44.tar.xz |
bpf: fix cb access in socket filter programs
eBPF socket filter programs may see junk in 'u32 cb[5]' area,
since it could have been used by protocol layers earlier.
For socket filter programs used in af_packet we need to clean
20 bytes of skb->cb area if it could be used by the program.
For programs attached to TCP/UDP sockets we need to save/restore
these 20 bytes, since it's used by protocol layers.
Remove SK_RUN_FILTER macro, since it's no longer used.
Long term we may move this bpf cb area to per-cpu scratch, but that
requires addition of new 'per-cpu load/store' instructions,
so not suitable as a short term fix.
Fixes: d691f9e8d440 ("bpf: allow programs to write to certain skb fields")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/bpf')
-rw-r--r-- | kernel/bpf/verifier.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b074b23000d6..f8da034c2258 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2024,7 +2024,7 @@ static int convert_ctx_accesses(struct verifier_env *env) cnt = env->prog->aux->ops-> convert_ctx_access(type, insn->dst_reg, insn->src_reg, - insn->off, insn_buf); + insn->off, insn_buf, env->prog); if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) { verbose("bpf verifier is misconfigured\n"); return -EINVAL; |