From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6B8482F2377; Tue, 17 Jun 2025 16:00:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750176038; cv=none; b=BJbfysSv7qVI7MWx1wjL97Y/a9mFrTsSaIX9/HXgF7Pz9QpthNmsH3sUHuWVUhrKKpR9k3/jBzkUeCWiODn7xOph3tI15m0zxNBRe9/9EQMYiJSfLOtdmv9R1zhIShdO16pqzQeMbUsDEpZqN7Aj6ZgBGGV16e0qY3erU37R4JE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750176038; c=relaxed/simple; bh=BD+Z2vgxbqUSzYLtp0r3YcS0SgLugvjl2Gh/jykWZQs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=INugCel15FoD9M48bZpRqTiMwujdZdaT0YR5WblqYVXMD8gwGlBk3D1iET5h1ui41JmUpF0KDSFG7+lVw1j/og6FrMcTwAONb/+ZeKbrGX7E8vyp1XOdIXHO/Bo7A00Y0YbD8yyGT9rbCg2daSCqMc0/9c4J9DXwC4e3mSw7QLQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=q8oeYKC7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="q8oeYKC7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCCFAC4CEF2; Tue, 17 Jun 2025 16:00:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750176038; bh=BD+Z2vgxbqUSzYLtp0r3YcS0SgLugvjl2Gh/jykWZQs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q8oeYKC7O8KrqKw3KnJc05/zHB8CHPldTLIcVBoGU0isv1r9MrrcHVPFE4L0UDCcQ qfPfc3hjahb+vnijEjcvenwDok+1YKosEPyKEKsfS0cbDEUmrdj4iCPqTTyrHe45ae C0VG4FQ81kgv6yEhinYK/Dv8DCndlzDm74q0qJec= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xuewen Yan , Di Shen , Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.12 190/512] bpf: Revert "bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic" Date: Tue, 17 Jun 2025 17:22:36 +0200 Message-ID: <20250617152427.337615774@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152419.512865572@linuxfoundation.org> References: <20250617152419.512865572@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Di Shen [ Upstream commit 4e2e6841ff761cc15a54e8bebcf35d7325ec78a2 ] This reverts commit 4a8f635a6054. Althought get_pid_task() internally already calls rcu_read_lock() and rcu_read_unlock(), the find_vpid() was not. The documentation for find_vpid() clearly states: "Must be called with the tasklist_lock or rcu_read_lock() held." Add proper rcu_read_lock/unlock() to protect the find_vpid(). Fixes: 4a8f635a6054 ("bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic") Reported-by: Xuewen Yan Signed-off-by: Di Shen Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20250520054943.5002-1-xuewen.yan@unisoc.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- kernel/trace/bpf_trace.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 66075e86b691c..3ec7df7dbeec4 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3349,7 +3349,9 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr } if (pid) { + rcu_read_lock(); task = get_pid_task(find_vpid(pid), PIDTYPE_TGID); + rcu_read_unlock(); if (!task) { err = -ESRCH; goto error_path_put; -- 2.39.5