Re: [PATCH bpf 2/2] selftests/bpf: Cover rdonly_cast dynptr slice lifetime

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Multi-line comments do not follow the BPF subsystem comment style guidelines. The opening `/*` must be on its own line.
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commit 23e88c2468fdbcf78bd114cff5b73d79a87a4337
Author: Nuoqi Gui <gnq25@mails.tsinghua.edu.cn>

selftests/bpf: Cover rdonly_cast dynptr slice lifetime

This commit adds verifier tests for bpf_rdonly_cast() alias lifetime. It
covers casting a ringbuf dynptr slice, releasing the dynptr, reading through
the cast alias, and stack-overwrite invalidations.

> diff --git a/tools/testing/selftests/bpf/progs/dynptr_fail.c b/tools/testing/selftests/bpf/progs/dynptr_fail.c
> index b62773ce5219b..7ffe55ba28663 100644
> --- a/tools/testing/selftests/bpf/progs/dynptr_fail.c
> +++ b/tools/testing/selftests/bpf/progs/dynptr_fail.c

[ ... ]

> +/* A read-only cast alias from an overwritten dynptr should be invalidated
> + * even when a clone still holds the underlying reference.
> + */
> +SEC("?raw_tp")
> +__failure __msg("invalid mem access 'scalar'")
> +int dynptr_rdonly_cast_slice_after_overwrite(void *ctx)

[Severity: Low]
This isn't a bug, but does this multi-line comment follow the preferred
BPF subsystem style? The opening /* is typically expected to be on its
own line.

[ ... ]

> +/* A read-only cast alias from a clone should remain valid after overwriting
> + * the original dynptr while the clone still holds the reference.
> + */
> +SEC("?raw_tp")
> +__success
> +int dynptr_rdonly_cast_clone_slice_after_parent_overwrite(void *ctx)

[Severity: Low]
This isn't a bug, but similar to the comment above, should the opening /*
be placed on its own line to match the expected multi-line comment style
for the BPF subsystem?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260615-f01-09-rdonly-cast-dynptr-lifetime-v1-0-2dd0a369e153@mails.tsinghua.edu.cn?part=2