From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta1.migadu.com (out-172.mta1.migadu.com [95.215.58.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A4173D7D82 for ; Mon, 30 Mar 2026 13:55:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774878933; cv=none; b=h8nSEG47QyRl6As/De0HMhcuJ2kt8ial5xMV1zYuw2zlDFGXbrbcRD0zASoEF6Vh0L2OioVCCgaIQI6imFO5PtFtm5jURhZiPvc8f6BVwaqT4wL+JOp5CkOB72CI+wtyrEQ3yWA3jRkS0zqI4SBBPC0Vw6f05G4GCdYINp4kqaw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774878933; c=relaxed/simple; bh=JuzlJXEAHGcSiF6n+n3yInCM4todvtFnYHvB3lvFcrs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NRoWyOCNtCCmAf0Ls5FBGcvOAoOx1YHT+b1faheCHDu1+9CeDoLG9n7uQl3SNDk1S/ysLRChXa1eeFMnwWyPMOorN/C1b6kGYjx/m3Z/URkLaUAK3Zsd6OdMJrKan5EIsRUtsoF2ZCVDbP6xKVyLfhUfozKsgd5PgnYRRBnrbGo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=qDWaEm9+; arc=none smtp.client-ip=95.215.58.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="qDWaEm9+" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1774878926; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8Oe2X5q/5SHXJHJJnjteGS61bN/fIuINUCylSG5ydx4=; b=qDWaEm9+oGVVjbVmrl8Z31/SC85DF2KQ+is//Zhbm9jWFgjFDtcN1k5WYLoJYlAPCQ3nWX FjngGBEVHXsZJJk8hrVEpcw/2nL8IKi0tGg1wWcwXzbP8VUYsjW8JLP4m+SYaV9rTJvA1s Nx7DGI+a+0EJn9VyWvlIZTMOOxOwuSs= Date: Mon, 30 Mar 2026 21:55:02 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH bpf-next v2 2/2] selftests/bpf: Add test to verify the fix of kprobe_write_ctx abuse To: Jiri Olsa Cc: bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Shuah Khan , Feng Yang , Toke Hoiland-Jorgensen , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com References: <20260326141718.17731-1-leon.hwang@linux.dev> <20260326141718.17731-3-leon.hwang@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Leon Hwang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 2026/3/30 17:28, Jiri Olsa wrote: > On Thu, Mar 26, 2026 at 10:17:18PM +0800, Leon Hwang wrote: > > SNIP > >> + prog_fd = bpf_program__fd(skel_kprobe->progs.kprobe_write_ctx); >> + bpf_program__set_attach_target(prog_ext, prog_fd, "kprobe_write_ctx"); >> + >> + err = kprobe_write_ctx__load(skel_ext); >> + if (!ASSERT_OK(err, "kprobe_write_ctx__load ext")) >> + goto out; >> + >> + prog_fd = bpf_program__fd(prog_kprobe); >> + link_ext = bpf_program__attach_freplace(prog_ext, prog_fd, "kprobe_dummy"); >> + ASSERT_ERR_PTR(link_ext, "bpf_program__attach_freplace link"); >> + ASSERT_EQ(errno, EINVAL, "bpf_program__attach_freplace errno"); > > nit, I prefer libbpf_get_error call instead, because it's not obvious > that ASSERT_ERR_PTR sets errno, smth like: > > if (!ASSERT_EQ(libbpf_get_error(link_ext), -EINVAL, .. > Yeah, libbpf_get_error() is better. Will use it. > anyway lgtm > > Acked-by: Jiri Olsa > Thanks for your review. Thanks, Leon [...]