Re: [PATCH bpf-next v2 3/3] selftests/bpf: guarantee zero termination for veristat test buffers

> selftests/bpf: guarantee zero termination for veristat test buffers
>
> In veristat tests replace direct read() calls with calls to
> read_output() utility function, which:
> - guarantees that the input buffer is zero terminated;
> - asserts that read operation succeeded.
>
> Signed-off-by: Eduard Zingerman <[email protected]>

This looks like a bug fix rather than just a cleanup. The pre-existing
code called read() on a buffer that was never zero terminated, then passed
it to __CHECK_STR() which expands to strstr(). Because init_fixture() and
teardown_fixture() reuse the same malloc()'d buffer across subtests,
strstr() could match text from a previous run and report a false PASS, or
read past the buffer end.

Should this include a Fixes tag pointing to the commit that added the
veristat subtests with the unterminated read() calls?


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CI run summary: https://github.com/kernel-patches/bpf/actions/runs/31753097393