Re: [PATCH bpf 2/2] selftests/bpf: Add return value tests for lsm cgroup

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] BPF test programs for the `socket_create` LSM hook incorrectly declare `struct task_struct *task` as their argument instead of `int family`.
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commit b7003df7335bb1051987324aa639e3088d3673b5
Author: Xu Kuohai <xukuohai@huawei.com>

selftests/bpf: Add return value tests for lsm cgroup

This commit adds tests to check return values set by the bpf_set_retval()
helper for lsm cgroup programs.

> diff --git a/tools/testing/selftests/bpf/progs/verifier_lsm.c b/tools/testing/selftests/bpf/progs/verifier_lsm.c
> index 38e8e91768620..2072671ed6439 100644
> --- a/tools/testing/selftests/bpf/progs/verifier_lsm.c
> +++ b/tools/testing/selftests/bpf/progs/verifier_lsm.c

[ ... ]

> @@ -188,4 +188,49 @@ int BPF_PROG(null_check, struct file *file)
>  	return 0;
>  }
>  
> +SEC("lsm_cgroup/socket_create")
> +__description("lsm_cgroup with -4095~0 retval test 1")
> +__success
> +int BPF_PROG(lsm_cgroup_set_retval_zero_valid, struct task_struct *task)

[Severity: Low]
Is this argument type correct for the socket_create hook? The LSM hook for
socket_create expects (int family, int type, int protocol, int kern), so
the first argument should be int family.

Using struct task_struct *task incorrectly casts the first integer argument
to a pointer. While it works here because the argument isn't dereferenced,
could this cause issues if this code is used as a template and the argument
is accessed in other tests?

> +{
> +	bpf_set_retval(0);
> +	return 0;
> +}

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260523085806.417723-1-xukuohai@huaweicloud.com?part=2