From: "Alexei Starovoitov" <alexei.starovoitov@gmail.com>
To: <sashiko-reviews@lists.linux.dev>
Cc: <bpf@vger.kernel.org>
Subject: Re: [PATCH bpf-next v2 02/15] selftests/bpf: Add tests for ALU on pointers with CAP_PERFMON
Date: Sat, 03 Oct 2026 11:48:17 +0000 [thread overview]
Message-ID: <DLV6H1CSHK76.14LXBR533VMQJ@gmail.com> (raw)
In-Reply-To: <20261002130803.A0FFA1F000FF@smtp.kernel.org>
On Fri, Oct 02, 2026 at 01:08 PM sashiko-bot@kernel.org <sashiko-bot@kernel.org> wrote:
> Additionally, since this program places multiple unprivileged operations
> sequentially, wouldn't the verifier abort at the first failure (r1 &= 1),
> leaving the unprivileged rejection of the subsequent operations (>>=, |=, ^=)
> completely untested?
Not an issue. Nothing changes for unpriv. to_scalar is false without
allow_ptr_leaks.
>> + r1 = 7; \
>> + r1 *= r0; \
>
> [Severity: Medium]
> Does this actually test the verifier's handling of pointer *= scalar?
>
> The multiplication is applied to a scalar destination (r1) with a pointer
> source (r0). Would it be more accurate to test if applying *= to a pointer
> destination correctly downgrades the pointer to a scalar?
No. The test is "number op= pointer". That's dst_reg != ptr_reg case.
pointer op= number is covered by other tests in this file.
next prev parent reply other threads:[~2026-10-03 11:48 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-02 12:46 [PATCH bpf-next v2 00/15] bpf: Support programs compiled by rust-bpf Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 01/15] bpf: Allow bitwise ops, shifts and mul/div on pointers with CAP_PERFMON Alexei Starovoitov
2026-10-02 13:49 ` bot+bpf-ci
2026-10-02 12:47 ` [PATCH bpf-next v2 02/15] selftests/bpf: Add tests for ALU " Alexei Starovoitov
2026-10-02 13:08 ` sashiko-bot
2026-10-03 11:48 ` Alexei Starovoitov [this message]
2026-10-02 12:47 ` [PATCH bpf-next v2 03/15] bpf: Treat load and store through a number as arena access Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 04/15] selftests/bpf: Add tests for arena access through numbers Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 05/15] bpf: Allow names of Rust types and functions in BTF Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 06/15] selftests/bpf: Add tests for " Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 07/15] bpf: Allow arguments without names in static " Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 08/15] selftests/bpf: Add test for arguments without names in static functions Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 09/15] bpf: Allow a variable in DATASEC that is smaller than its type Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 10/15] bpftool: Skip pieces of variables in DATASEC Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 11/15] selftests/bpf: Add tests for a variable that is smaller than its type Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 12/15] libbpf: Keep global data in arena when the object has .arena.data Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 13/15] libbpf: Keep format strings of bpf_printk() in .rodata.str Alexei Starovoitov
2026-10-02 12:47 ` [PATCH bpf-next v2 14/15] selftests/bpf: Add test for global data in arena Alexei Starovoitov
2026-10-02 13:49 ` bot+bpf-ci
2026-10-02 12:47 ` [PATCH bpf-next v2 15/15] selftests/bpf: Add test for global data of a program in Rust Alexei Starovoitov
2026-10-03 1:33 ` sashiko-bot
2026-10-03 11:47 ` Alexei Starovoitov
2026-10-03 14:20 ` [PATCH bpf-next v2 00/15] bpf: Support programs compiled by rust-bpf patchwork-bot+netdevbpf
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