From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f69.google.com (mail-oo1-f69.google.com [209.85.161.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 51FB436493C for ; Fri, 27 Feb 2026 06:40:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772174427; cv=none; b=DWwf3LJzBUtCOhD/a67XHucXCGqwCMlbdVS0vRR2CH7LZja0pHus1En4UnW84M2NqiGHRL+iszIczsprCpD85XMNVVNAE9oLQgpt7sHnxiQ03dxzVLkQK1YKflmPBVbumX5YcyvM6GNug4wPxFsAP0XPBnbMwum3XIH6D8Dh8gs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772174427; c=relaxed/simple; bh=KHpV5XnveDHMB9aDeTn9wHnix7sIYMgCQ4A+9Ud+8ko=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=keGzgAIgNr9oUCzYkUuPEChVyqiEPee475aeqi3y4T6Hx8jMiEE3Xd/L94KiGqWPmpOnkK4ZEjH5cEc2eZ8EOhsntEWL+OtQHiKzWG1tZzhGz4joyJtu0LYdVrhPAnA521wTtz5hyVGBZnTo8L8nmX3RC0+hhodSqsxfhDJinx8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f69.google.com with SMTP id 006d021491bc7-66308f16ea1so13918016eaf.2 for ; Thu, 26 Feb 2026 22:40:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772174425; x=1772779225; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=K/m3ThhOi9BghI3jEmSvcKXHlRO+J/KF0TB2yPf2e8A=; b=bAzxYu+LmaXH298gIWDz9ugvaCroKsQrBJpeeL2smSEnbNsZiLDz08z7x17useSBbK C/hyUHB0q6gvmghxf8XHd2V8LL+2iGbjjmMV4wP96ebqo+T6sLjaShn/KXBKnWC+v6Ys VpB3n1F9ijjcj+ROwbsAe31/cdCORpJq+isWJKFhJNYAovZz/rnJ2BvIwqNxA8Qh9IF9 iJcU9n9k2D1VzLQ9bJSFzcR2NsbdTWvFCnz9HIqwtI9863RA+SzGOpSnE+52PIFYQOrh ZJPnA1PgzWc0IW5VuJ04e3v/UXt/FjkizQObZp1hREFKS/EYwOzTkv5qMTjwEBPNogJ+ OPEQ== X-Forwarded-Encrypted: i=1; AJvYcCV6shZnfuaxgREYBfvT4vmSVSDfiH8mz6ruV3CrZP2K7gD63/S1gb6X084T+gXfk1DM+6octPE=@vger.kernel.org X-Gm-Message-State: AOJu0Yy4pTL3DWyJpAg3gL3cGrEMvXu53L1Cz2ufgLJeYKmcRydDFQ7n DRXK7GRwq++n/Cdl8MR3SqNwvwLYbiAjfsAM+Qb4n7tXzJS0T0T4qKauqzwcsyzRzYEH8dxm9Fc VcTrLbBbn33vXs/+wEVUPsKL+ij/iMiXCxlsgy1+NL3BPOMgb7eNSNIbCBVw= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:81d0:b0:679:975b:f224 with SMTP id 006d021491bc7-679fae0ac83mr1456374eaf.18.1772174425275; Thu, 26 Feb 2026 22:40:25 -0800 (PST) Date: Thu, 26 Feb 2026 22:40:25 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69a13c59.050a0220.3a55be.0015.GAE@google.com> Subject: [syzbot] [wireless?] possible deadlock in ieee80211_change_mac (4) From: syzbot To: johannes@sipsolutions.net, linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: d4f687fbbce4 ovpn: tcp - fix packet extraction from stream git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=1763544a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=665cbf0979cda6c5 dashboard link: https://syzkaller.appspot.com/bug?extid=1b20ba3b6d47543a7742 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ee42a61b2ee7/disk-d4f687fb.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e5470ff18ff8/vmlinux-d4f687fb.xz kernel image: https://storage.googleapis.com/syzbot-assets/d50957aaabf2/bzImage-d4f687fb.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1b20ba3b6d47543a7742@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.4107/21056 is trying to acquire lock: ffff888055af0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline] ffff888055af0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_change_mac+0xb5/0x1410 net/mac80211/iface.c:324 but task is already holding lock: ffffffff8fbc12b0 (dev_addr_sem){++++}-{4:4}, at: do_setlink+0x806/0x4590 net/core/rtnetlink.c:3105 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (dev_addr_sem){++++}-{4:4}: down_read+0x47/0x2e0 kernel/locking/rwsem.c:1537 address_show+0x25/0x250 net/core/net-sysfs.c:266 dev_attr_show+0x58/0xc0 drivers/base/core.c:2421 sysfs_kf_seq_show+0x310/0x490 fs/sysfs/file.c:65 seq_read_iter+0x4ef/0xe10 fs/seq_file.c:231 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x582/0xa70 fs/read_write.c:574 ksys_read+0x150/0x270 fs/read_write.c:717 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (kn->active#13){++++}-{0:0}: kernfs_drain+0x284/0x600 fs/kernfs/dir.c:511 __kernfs_remove+0x3cf/0x660 fs/kernfs/dir.c:1513 kernfs_remove_by_name_ns+0xaf/0x130 fs/kernfs/dir.c:1722 kernfs_remove_by_name include/linux/kernfs.h:633 [inline] remove_files fs/sysfs/group.c:28 [inline] sysfs_remove_group+0xfc/0x2e0 fs/sysfs/group.c:328 sysfs_remove_groups+0x54/0xb0 fs/sysfs/group.c:352 device_remove_groups drivers/base/core.c:2843 [inline] device_remove_attrs+0x229/0x280 drivers/base/core.c:2979 device_del+0x51f/0x8f0 drivers/base/core.c:3877 unregister_netdevice_many_notify+0x1e0e/0x2370 net/core/dev.c:12438 unregister_netdevice_many net/core/dev.c:12466 [inline] unregister_netdevice_queue+0x31f/0x360 net/core/dev.c:12280 unregister_netdevice include/linux/netdevice.h:3408 [inline] _cfg80211_unregister_wdev+0x155/0x570 net/wireless/core.c:1297 ieee80211_remove_interfaces+0x49c/0x6d0 net/mac80211/iface.c:2440 ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1691 mac80211_hwsim_del_radio+0x28a/0x490 drivers/net/wireless/virtual/mac80211_hwsim.c:5916 remove_user_radios drivers/net/wireless/virtual/mac80211_hwsim.c:6727 [inline] mac80211_hwsim_netlink_notify+0xfae/0x1310 drivers/net/wireless/virtual/mac80211_hwsim.c:6741 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 netlink_release+0x123b/0x1ad0 net/netlink/af_netlink.c:761 __sock_release net/socket.c:662 [inline] sock_close+0xc3/0x240 net/socket.c:1455 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2807 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&rdev->wiphy.mtx){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 class_wiphy_constructor include/net/cfg80211.h:6441 [inline] ieee80211_change_mac+0xb5/0x1410 net/mac80211/iface.c:324 netif_set_mac_address+0x317/0x4e0 net/core/dev.c:9989 do_setlink+0x9b1/0x4590 net/core/rtnetlink.c:3110 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x15a9/0x1be0 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &rdev->wiphy.mtx --> kn->active#13 --> dev_addr_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(dev_addr_sem); lock(kn->active#13); lock(dev_addr_sem); lock(&rdev->wiphy.mtx); *** DEADLOCK *** 2 locks held by syz.0.4107/21056: #0: ffffffff8fbcb808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fbcb808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8fbcb808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 #1: ffffffff8fbc12b0 (dev_addr_sem){++++}-{4:4}, at: do_setlink+0x806/0x4590 net/core/rtnetlink.c:3105 stack backtrace: CPU: 0 UID: 0 PID: 21056 Comm: syz.0.4107 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x19f/0x1300 kernel/locking/mutex.c:776 class_wiphy_constructor include/net/cfg80211.h:6441 [inline] ieee80211_change_mac+0xb5/0x1410 net/mac80211/iface.c:324 netif_set_mac_address+0x317/0x4e0 net/core/dev.c:9989 do_setlink+0x9b1/0x4590 net/core/rtnetlink.c:3110 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x15a9/0x1be0 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f909439c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f90951b3028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9094616090 RCX: 00007f909439c629 RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000000000000004 RBP: 00007f9094432b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9094616128 R14: 00007f9094616090 R15: 00007fff601b4778 netlink: 8 bytes leftover after parsing attributes in process `syz.0.4107'. netlink: 'syz.0.4107': attribute type 5 has an invalid length. netlink: 20 bytes leftover after parsing attributes in process `syz.0.4107'. geneve2: entered promiscuous mode geneve2: entered allmulticast mode --- This report is generated by a bot. 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