From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C6A5B446C06; Thu, 30 Jul 2026 15:21:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424873; cv=none; b=WlCHag5CxAzyAMSZQCLMwZ38iZH3LH3ToRnp3uXTV8KN+kXEVwOaKTjO73zY7Zj5YaI+V9cn2X192QDTzDYZs0vb9vNS3aXx0itmkYbIIufOyI/Gx8en8Wmen/T+vCxmD6Ym35E6TM+Uiew4AqfZwHQaaO6sBNotkYpHBTjBMfM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424873; c=relaxed/simple; bh=7zmJPYSNfR2wDUNmEQpTWqGjFhu6JvbAQAPtQrlUtlk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eFwtfQGjKUSyFBpMi/TdbFJYJs5ZfWbytNoiAL2kjNVYt6cpebJN3rMy6mWzn+LVK5mvVYBKdeuxgSRgzDV7HfmDWFQfHzddo19IsqoqmHzhImSWGsdnSrxNcB+vsptWsPha6iDDOgsn5rCVHhFo++nMAQjrWXduPgYziflsUgs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=b3AcObsl; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="b3AcObsl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2A13F1F0155E; Thu, 30 Jul 2026 15:21:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785424871; bh=p/KrA3XxuVUFALPWFGyTd/ggU5dWZpqciYG0ZVusEtI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=b3AcObsl10oG90sgprhwNYxzdIu9rGlM7lWgdQ4jc6Yl2dugNzhmKbui/KuFWG7SR J23AgRUzMS4fw41xFi+km5y8LjQIvMCnYn4BFrUJcp8jhkyGAYoJTAR1QrxUKn+iUZ xHFNnNuOLwP5/z5mbS4SPXD6Bry4Gg5/WRrmhAC8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Magnus Lindholm , Jann Horn , "Christian Brauner (Amutable)" Subject: [PATCH 6.18 544/675] proc: Fix broken error paths for namespace links Date: Thu, 30 Jul 2026 16:14:34 +0200 Message-ID: <20260730141456.705835044@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jann Horn commit 425224c2d700391729be7fe6929a88ef4e2d7a4e upstream. Don't return the return value of down_read_killable() (0) when a ptrace access check fails, return -EACCES as intended. Reported-by: Magnus Lindholm Closes: https://lore.kernel.org/r/20260706170735.2941493-1-linmag7@gmail.com Fixes: 6650527444da ("proc: protect ptrace_may_access() with exec_update_lock (part 1)") Cc: stable@vger.kernel.org Signed-off-by: Jann Horn Link: https://patch.msgid.link/20260706-procfs-ns-eacces-fix-v1-1-a69ab14c02e6@google.com Tested-by: Magnus Lindholm Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Greg Kroah-Hartman --- fs/proc/namespaces.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/proc/namespaces.c +++ b/fs/proc/namespaces.c @@ -46,7 +46,7 @@ static const char *proc_ns_get_link(stru const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops; struct task_struct *task; struct path ns_path; - int error = -EACCES; + int error; if (!dentry) return ERR_PTR(-ECHILD); @@ -59,6 +59,7 @@ static const char *proc_ns_get_link(stru if (error) goto out_put_task; + error = -EACCES; if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) goto out; @@ -90,6 +91,7 @@ static int proc_ns_readlink(struct dentr if (res) goto out_put_task; + res = -EACCES; if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { res = ns_get_name(name, sizeof(name), task, ns_ops); if (res >= 0)