bpf, verifier: detect misconfigured mem, size argument pair

Browse source

I've seen two patch proposals now for helper additions that used
ARG_PTR_TO_MEM or similar in reg_X but no corresponding ARG_CONST_SIZE
in reg_X+1. Verifier won't complain in such case, but it will omit
verifying the memory passed to the helper thus ending up badly.
Detect such buggy helper function signature and bail out during
verification rather than finding them through review.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

...

This commit is contained in:

Daniel Borkmann 2018-01-20 01:24:29 +01:00 • committed by Alexei Starovoitov

parent 417f1d9f21

commit 9013341594

1 changed files with 55 additions and 24 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

79

kernel/bpf/verifier.c

View file