tree e690fffd9a8cf58bc68b3b35e0d7966b73e610d1
parent d15eccea69b96a5116169688dcc9baf6d1ce2751
author Alexei Starovoitov <ast@fb.com> 1466028053 -0700
committer Alexei Starovoitov <ast@fb.com> 1466029897 -0700

bpf: fix matching of data/data_end in verifier

The ctx structure passed into bpf programs is different depending on bpf
program type. The verifier incorrectly marked ctx->data and ctx->data_end
access based on ctx offset only. That caused loads in tracing programs
int bpf_prog(struct pt_regs *ctx) { .. ctx->ax .. }
to be incorrectly marked as PTR_TO_PACKET which later caused verifier
to reject the program that was actually valid in tracing context.
Fix this by doing program type specific matching of ctx offsets.

Fixes: 969bf05eb3ce ("bpf: direct packet access")
Reported-by: Sasha Goldshtein <goldshtn@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>