From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-179.mta0.migadu.com (out-179.mta0.migadu.com [91.218.175.179]) (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 D9A5F1F12E0 for ; Tue, 21 Jul 2026 13:31:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784640702; cv=none; b=MPBn+B5+yC+c7+bhAtRT0Z4auzezjkMN3Z4d+CVuV5HspvsFVQM9mCcubtkK36cmPKU7Z7kwoJMF9XwSk0bbjYCdEe1b0FdDGAc3p/0i8I3BTWIaWhhKtYI0BChzKynwa17cm2sx+fqG4hmvphKWEIH+a6rwVDhWeg9lU9Gt9Is= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784640702; c=relaxed/simple; bh=1Y4uCMaWFJ2YnJaUqugry8zOJdoCsJRnngLRIjXh9HQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=gNUgTMhufQGNcsfX88UXQTmJlpOTdN6UogwsU94Duut+nNQgC24SoO6EgEAKEavDlbpSPpElWaPfpXBuqpAYao/JLVubsGx2nmRCTiZAkeuM6feOTEr3S5Z25DNS44/GOVxjsmrP3aovXIsk03OmIMiSKGqrWWXlZXhKncx5yug= 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=Sbkg0ZT9; arc=none smtp.client-ip=91.218.175.179 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="Sbkg0ZT9" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784640695; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=UwoXfTfmep5EjRgLUdZq4lvJY8DxeJwoomAY6JwLMhg=; b=Sbkg0ZT9yL05MUIRhsvWH1vTL5S+7q8qMZNiD5MNMRJsASOsrB/ZtOu0fZP3p63PnCq1zW XWlCkLFpJFIJp14QlEBFus0/LQT3cGMqF9ud4+hbvHsSDnl2aV4/P7agtXzPptf4STxizO d2N2t42eiUtitsP78jctk+bth/4RRG8= From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Martin KaFai Lau , Song Liu , Yonghong Song , Jiri Olsa , Emil Tsalapatis , Shuah Khan , Jingguo Tan , Pu Lehui , Leon Hwang , Lin Ma , Maciej Fijalkowski , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-patches-bot@fb.com Subject: [PATCH bpf-next 0/2] bpf: Fix WARNING in bpf_tracing_link_release Date: Tue, 21 Jul 2026 21:30:33 +0800 Message-ID: <20260721133036.49265-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT The trampoline could be corrupted by the blindly 'tr->flags = BPF_TRAMP_F_TAIL_CALL_CTX' in verifier. 1. A fexit attached to a tail_call_reachable prog. 2. Another fexit loaded with the same tail_call_reachable prog target. 3. Close the first fexit link. [ 3.410719] WARNING: kernel/bpf/syscall.c:3551 at bpf_tracing_link_release+0x53/0x60, CPU#1: test_progs/98 ... [ 3.428793] bpf_link_free+0x58/0x130 [ 3.429293] bpf_link_release+0x23/0x30 Fix the warning by updating 'tr->flags' with '|=' and lock. Leon Hwang (2): bpf: Fix WARNING in bpf_tracing_link_release selftests/bpf: Verify no warning when close fexit link include/linux/bpf.h | 2 + kernel/bpf/trampoline.c | 7 +++ kernel/bpf/verifier.c | 2 +- .../selftests/bpf/prog_tests/tailcalls.c | 51 +++++++++++++++++++ 4 files changed, 61 insertions(+), 1 deletion(-) -- 2.55.0