From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9B68C004C0 for ; Mon, 23 Oct 2023 11:21:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233802AbjJWLVL (ORCPT ); Mon, 23 Oct 2023 07:21:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233805AbjJWLVL (ORCPT ); Mon, 23 Oct 2023 07:21:11 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26B4EC2 for ; Mon, 23 Oct 2023 04:21:09 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 390DEC433C8; Mon, 23 Oct 2023 11:21:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1698060068; bh=y1V6x49j5eH5EAlkGm4z5mH6JTb31Sgmn92hMfWmvJs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=znpGwKFV3zo4YzNwLYyDzy6jvdYCpzKep3giG1IirXWOmct7p/0LhSogpfEC/Nrw3 oQe+eXLtECmM5ur+MKwCqJMzUv6tlflhpt7k4kgfev2jozsXrU2igbX9wedxoTC4cH qXUMoE2tJnMKfQQhmn0Peo4z6/jagEQtvOGlt2oM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot , Eric Dumazet , Steffen Klassert Subject: [PATCH 6.1 047/196] xfrm: fix a data-race in xfrm_lookup_with_ifid() Date: Mon, 23 Oct 2023 12:55:12 +0200 Message-ID: <20231023104829.847320332@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231023104828.488041585@linuxfoundation.org> References: <20231023104828.488041585@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit de5724ca38fd5e442bae9c1fab31942b6544012d upstream. syzbot complains about a race in xfrm_lookup_with_ifid() [1] When preparing commit 0a9e5794b21e ("xfrm: annotate data-race around use_time") I thought xfrm_lookup_with_ifid() was modifying a still private structure. [1] BUG: KCSAN: data-race in xfrm_lookup_with_ifid / xfrm_lookup_with_ifid write to 0xffff88813ea41108 of 8 bytes by task 8150 on cpu 1: xfrm_lookup_with_ifid+0xce7/0x12d0 net/xfrm/xfrm_policy.c:3218 xfrm_lookup net/xfrm/xfrm_policy.c:3270 [inline] xfrm_lookup_route+0x3b/0x100 net/xfrm/xfrm_policy.c:3281 ip6_dst_lookup_flow+0x98/0xc0 net/ipv6/ip6_output.c:1246 send6+0x241/0x3c0 drivers/net/wireguard/socket.c:139 wg_socket_send_skb_to_peer+0xbd/0x130 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0xd6/0x100 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x10c/0x150 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 write to 0xffff88813ea41108 of 8 bytes by task 15867 on cpu 0: xfrm_lookup_with_ifid+0xce7/0x12d0 net/xfrm/xfrm_policy.c:3218 xfrm_lookup net/xfrm/xfrm_policy.c:3270 [inline] xfrm_lookup_route+0x3b/0x100 net/xfrm/xfrm_policy.c:3281 ip6_dst_lookup_flow+0x98/0xc0 net/ipv6/ip6_output.c:1246 send6+0x241/0x3c0 drivers/net/wireguard/socket.c:139 wg_socket_send_skb_to_peer+0xbd/0x130 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0xd6/0x100 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x10c/0x150 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x00000000651cd9d1 -> 0x00000000651cd9d2 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 15867 Comm: kworker/u4:58 Not tainted 6.6.0-rc4-syzkaller-00016-g5e62ed3b1c8a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker Fixes: 0a9e5794b21e ("xfrm: annotate data-race around use_time") Reported-by: syzbot Signed-off-by: Eric Dumazet Cc: Steffen Klassert Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_policy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3138,7 +3138,7 @@ no_transform: } for (i = 0; i < num_pols; i++) - pols[i]->curlft.use_time = ktime_get_real_seconds(); + WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds()); if (num_xfrms < 0) { /* Prohibit the flow */