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 X-Spam-Level: X-Spam-Status: No, score=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BB95C35247 for ; Mon, 3 Feb 2020 22:08:32 +0000 (UTC) Received: from krantz.zx2c4.com (krantz.zx2c4.com [192.95.5.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0638E20674 for ; Mon, 3 Feb 2020 22:08:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0638E20674 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=wireguard-bounces@lists.zx2c4.com Received: from krantz.zx2c4.com (localhost [IPv6:::1]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id ad5bbf42; Mon, 3 Feb 2020 22:07:32 +0000 (UTC) Received: from krantz.zx2c4.com (localhost [127.0.0.1]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id a4e8a757 for ; Mon, 3 Feb 2020 22:07:29 +0000 (UTC) Received: from mail-il1-f197.google.com (mail-il1-f197.google.com [209.85.166.197]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id e1a58377 for ; Mon, 3 Feb 2020 22:07:29 +0000 (UTC) Received: by mail-il1-f197.google.com with SMTP id x69so13187351ill.14 for ; Mon, 03 Feb 2020 14:08:12 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=Fl+mqf7SXbDA+ahGJYdNPGegyPt8l79GHARMg/wdaAs=; b=IYQI6SXwIFeO97LJqhCTB2TKS5t01tjTcvmbCKvbyM/At3u7DdGAxJESawvIFncFpe QiJWU9kFJksTQP6o6Qk0gF+EdxDuq/W7n5mTbl/aVPgEfxPKVapww8pJ55rbDw86LK8I YbfWmd4yk+Cej8Sic3zV5r5lnkj8DD/w3XLXlnv+6xRcahxc69IvwyCx7bPQKpRjYdDz 50lH85cWmaM1ifRVjmeTipGol+n+1OodoGTJv4b7wS+xJgHZvqaiwyhc1k52epKvvCiG /p5eEhlCFVTqt1c3GLu49J+ZJ1v9V46ZUtPrWu+k0/k18HeXitpX8YrqFzwZbDsMYIxb 77Kg== X-Gm-Message-State: APjAAAXFPUYH8UYCvbmz+jjd4eyPB9SSSMVE/ye0VI3U9lsg4eCN0/mv pAp7XT1p8zuytCClQLUFVCSavv+H5hLkb6yeYL4bf2I61CIB X-Google-Smtp-Source: APXvYqyQ+w9fm6B/HIwRnHtRDk2vjXzNHeQ1F3vNZIncW6vp9VQKkMODARcwAdWPAHzG6DjcnOeyZrGypXGWCmtfI4/BLtOOD23e MIME-Version: 1.0 X-Received: by 2002:a02:81cc:: with SMTP id r12mr20424294jag.93.1580767692501; Mon, 03 Feb 2020 14:08:12 -0800 (PST) Date: Mon, 03 Feb 2020 14:08:12 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000c8bcba059db3289b@google.com> Subject: possible deadlock in wg_set_device From: syzbot To: Jason@zx2c4.com, davem@davemloft.net, jason@zx2c4.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, wireguard@lists.zx2c4.com X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" Hello, syzbot found the following crash on: HEAD commit: 9f68e365 Merge tag 'drm-next-2020-01-30' of git://anongit... git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=11b068b5e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=95b275782b150c86 dashboard link: https://syzkaller.appspot.com/bug?extid=42d05aefd7fce69f968f compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1087e9bee00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16c665bee00000 The bug was bisected to: commit e7096c131e5161fa3b8e52a650d7719d2857adfd Author: Jason A. Donenfeld Date: Sun Dec 8 23:27:34 2019 +0000 net: WireGuard secure network tunnel bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=15abc7c9e00000 final crash: https://syzkaller.appspot.com/x/report.txt?x=17abc7c9e00000 console output: https://syzkaller.appspot.com/x/log.txt?x=13abc7c9e00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+42d05aefd7fce69f968f@syzkaller.appspotmail.com Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") batman_adv: batadv0: Interface activated: batadv_slave_1 ====================================================== WARNING: possible circular locking dependency detected 5.5.0-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor962/10036 is trying to acquire lock: ffff8880a9696128 ((wq_completion)wg-kex-wireguard0){+.+.}, at: flush_workqueue+0xf7/0x14c0 kernel/workqueue.c:2772 but task is already holding lock: ffff88808ee54e80 (&wg->static_identity.lock){++++}, at: wg_set_device+0xe8b/0x1350 drivers/net/wireguard/netlink.c:567 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&wg->static_identity.lock){++++}: down_read+0x95/0x430 kernel/locking/rwsem.c:1495 wg_noise_handshake_create_initiation+0xc0/0x670 drivers/net/wireguard/noise.c:499 wg_packet_send_handshake_initiation+0x185/0x250 drivers/net/wireguard/send.c:34 wg_packet_handshake_send_worker+0x1d/0x30 drivers/net/wireguard/send.c:51 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}: process_one_work+0x972/0x17a0 kernel/workqueue.c:2240 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #0 ((wq_completion)wg-kex-wireguard0){+.+.}: check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 flush_workqueue+0x126/0x14c0 kernel/workqueue.c:2775 peer_remove_after_dead+0x16b/0x230 drivers/net/wireguard/peer.c:141 wg_peer_remove+0x244/0x340 drivers/net/wireguard/peer.c:176 wg_set_device+0xf76/0x1350 drivers/net/wireguard/netlink.c:575 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline] genl_family_rcv_msg net/netlink/genetlink.c:717 [inline] genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: (wq_completion)wg-kex-wireguard0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&wg->static_identity.lock); lock((work_completion)(&peer->transmit_handshake_work)); lock(&wg->static_identity.lock); lock((wq_completion)wg-kex-wireguard0); *** DEADLOCK *** 5 locks held by syz-executor962/10036: #0: ffffffff8a7899e8 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:744 #1: ffffffff8a789aa0 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8a789aa0 (genl_mutex){+.+.}, at: genl_rcv_msg+0x7de/0xea0 net/netlink/genetlink.c:732 #2: ffffffff8a733c80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 #3: ffff88808ee550a0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0x2be/0x1350 drivers/net/wireguard/netlink.c:510 #4: ffff88808ee54e80 (&wg->static_identity.lock){++++}, at: wg_set_device+0xe8b/0x1350 drivers/net/wireguard/netlink.c:567 stack backtrace: CPU: 0 PID: 10036 Comm: syz-executor962 Not tainted 5.5.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x163/0x172 kernel/locking/lockdep.c:1684 check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1808 check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 flush_workqueue+0x126/0x14c0 kernel/workqueue.c:2775 peer_remove_after_dead+0x16b/0x230 drivers/net/wireguard/peer.c:141 wg_peer_remove+0x244/0x340 drivers/net/wireguard/peer.c:176 wg_set_device+0xf76/0x1350 drivers/net/wireguard/netlink.c:575 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline] genl_family_rcv_msg net/netlink/genetlink.c:717 [inline] genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4491c9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 9b d4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcc45f9878 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000003064 RCX: 00000000004491c9 RDX: 0000000000000000 RSI: 0000000020001340 RDI: 0000000000000004 RBP: 7261756765726977 R08: 0000000000000000 R09: 0000000001bbbbb --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches _______________________________________________ WireGuard mailing list WireGuard@lists.zx2c4.com https://lists.zx2c4.com/mailman/listinfo/wireguard