Re: [PATCH bpf-next v2 2/2] selftests/bpf: Cover scalar add from rdonly untrusted memory

[bot+bpf-ci]

> selftests/bpf: Cover scalar add from rdonly untrusted memory
>
> Add a verifier test for scalar += rdonly_untrusted_mem. The program gets a
> read-only untrusted memory value from bpf_rdonly_cast(..., 0), adds it to a
> scalar destination, and then applies a bitwise operation to the result.
>
> The addition itself is allowed, but the result must be tracked as a
> pointer. The verifier should reject the following bitwise operation instead
> of preserving stale scalar state.
>
> Add coverage for scalar -= pointer and scalar ^= pointer as well. This
> prevents the early return from bypassing normal pointer ALU rejection.
>
> Signed-off-by: Nuoqi Gui <gnq25@xxxxxxxxxxxxxxxxxxxxx>

This selftest covers the early return in adjust_ptr_min_max_vals() that left
stale scalar state on the destination for scalar += rdonly_untrusted_mem,
which could let a later pointer ALU operation be accepted. That early return
came in with f2362a57aeff, and the companion functional fix carries a
Fixes: tag, but this selftest commit does not.

Should this include:

  Fixes: f2362a57aeff ("bpf: allow void* cast using bpf_rdonly_cast()")


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CI run summary: https://github.com/kernel-patches/bpf/actions/runs/27467222513