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author | Alexei Starovoitov <ast@fb.com> | 2016-04-12 10:26:19 -0700 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2016-07-10 23:07:21 -0400 |
commit | a4e1611c8bc5e331e07bea540d3571911df6ac52 (patch) | |
tree | 1c332e9a2a8e5d403d1304a60add298af49b3a2a /kernel | |
parent | 5730fd5d72071c9ae96929292351029ea56de7c0 (diff) | |
download | lwn-a4e1611c8bc5e331e07bea540d3571911df6ac52.tar.gz lwn-a4e1611c8bc5e331e07bea540d3571911df6ac52.zip |
bpf/verifier: reject invalid LD_ABS | BPF_DW instruction
[ Upstream commit d82bccc69041a51f7b7b9b4a36db0772f4cdba21 ]
verifier must check for reserved size bits in instruction opcode and
reject BPF_LD | BPF_ABS | BPF_DW and BPF_LD | BPF_IND | BPF_DW instructions,
otherwise interpreter will WARN_RATELIMIT on them during execution.
Fixes: ddd872bc3098 ("bpf: verifier: add checks for BPF_ABS | BPF_IND instructions")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/verifier.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 6582410a71c7..dd16d1993c04 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1227,6 +1227,7 @@ static int check_ld_abs(struct verifier_env *env, struct bpf_insn *insn) } if (insn->dst_reg != BPF_REG_0 || insn->off != 0 || + BPF_SIZE(insn->code) == BPF_DW || (mode == BPF_ABS && insn->src_reg != BPF_REG_0)) { verbose("BPF_LD_ABS uses reserved fields\n"); return -EINVAL; |