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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Virus-Scanned: Clear (ClamAV 1.4.3/28083/Wed Aug 5 08:24:50 2026) On 8/1/26 10:26 AM, 임준서 wrote: > Thanks for the review. > > The reproducer already sets ctx->optlen to a negative value (-11) in > the cgroup BPF program: > > /* ctx->optlen = -11; */ > BPF_MOV64_IMM(BPF_REG_2, -11), > BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_2, > offsetof(struct bpf_sockopt, optlen)), > > https://gist.github.com/ZirAjs/a177ec6d8f2c8ed7d93edca6313a9255 > > The PASS/FAIL output only checks the behavior before and after applying the > patch. Without the patch, the negative value reaches copy_to_sockptr() and > triggers the warning. With the patch, getsockopt() rejects it with -EFAULT. > > Would you prefer that I include the reproducer directly in the patch > submission rather than only linking to the gist? Yes, please add it as 2nd commit and check git log on how to integrate it into test_progs (tools/testing/selftests/bpf/) so it can run via CI. Thanks, Daniel