diff options
| author | Markus Kötter <nepenthesdev@gmail.com> | 2011-12-17 11:39:08 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-12-19 15:47:29 -0500 |
| commit | a03ffcf873fe0f2565386ca8ef832144c42e67fa (patch) | |
| tree | fd83a7eefe03946bba72c5a087d6c9aabb7aadb8 | |
| parent | d1388dacbbb1d1b2bc208a4ba18de9316dc49ce9 (diff) | |
net: bpf_jit: fix an off-one bug in x86_64 cond jump target
x86 jump instruction size is 2 or 5 bytes (near/long jump), not 2 or 6
bytes.
In case a conditional jump is followed by a long jump, conditional jump
target is one byte past the start of target instruction.
Signed-off-by: Markus Kötter <nepenthesdev@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index bfab3fa10ed..7b65f752c5f 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -568,8 +568,8 @@ cond_branch: f_offset = addrs[i + filter[i].jf] - addrs[i]; break; } if (filter[i].jt != 0) { - if (filter[i].jf) - t_offset += is_near(f_offset) ? 2 : 6; + if (filter[i].jf && f_offset) + t_offset += is_near(f_offset) ? 2 : 5; EMIT_COND_JMP(t_op, t_offset); if (filter[i].jf) EMIT_JMP(f_offset); |