syzbot


possible deadlock in cfg80211_netdev_notifier_call (3)

Status: upstream: reported on 2024/06/16 17:50
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+61f0f147bbf185cfa088@syzkaller.appspotmail.com
First crash: 36d, last: 14d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] possible deadlock in cfg80211_netdev_notifier_call (3) 0 (1) 2024/06/16 17:50
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in cfg80211_netdev_notifier_call (2) wireless 2 1154d 1165d 20/27 fixed on 2021/11/10 00:50
upstream possible deadlock in cfg80211_netdev_notifier_call wireless syz done 13 1197d 1263d 20/27 fixed on 2021/04/09 19:46

Sample crash report:
__nla_validate_parse: 4 callbacks suppressed
netlink: 55 bytes leftover after parsing attributes in process `syz.3.4018'.
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc5-syzkaller-00198-g9a0c28efeec6 #0 Not tainted
------------------------------------------------------
syz.3.4018/17170 is trying to acquire lock:
ffff888022abc768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5966 [inline]
ffff888022abc768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_netdev_notifier_call+0x308/0x1490 net/wireless/core.c:1524

but task is already holding lock:
ffff88802e624d20 (team->team_lock_key#7){+.+.}-{3:3}, at: team_add_slave+0xad/0x2750 drivers/net/team/team_core.c:1975

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (team->team_lock_key#7){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       team_port_change_check+0x51/0x1e0 drivers/net/team/team_core.c:2950
       team_device_event+0x161/0x5b0 drivers/net/team/team_core.c:2976
       notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
       call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
       call_netdevice_notifiers net/core/dev.c:2044 [inline]
       dev_close_many+0x33c/0x4c0 net/core/dev.c:1585
       unregister_netdevice_many_notify+0x544/0x16b0 net/core/dev.c:11194
       macvlan_device_event+0x7e0/0x870 drivers/net/macvlan.c:1828
       notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
       call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
       call_netdevice_notifiers net/core/dev.c:2044 [inline]
       unregister_netdevice_many_notify+0xd75/0x16b0 net/core/dev.c:11219
       unregister_netdevice_many net/core/dev.c:11277 [inline]
       unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11156
       unregister_netdevice include/linux/netdevice.h:3119 [inline]
       _cfg80211_unregister_wdev+0x162/0x560 net/wireless/core.c:1206
       ieee80211_if_remove+0x25d/0x3a0 net/mac80211/iface.c:2245
       ieee80211_del_iface+0x19/0x30 net/mac80211/cfg.c:202
       rdev_del_virtual_intf net/wireless/rdev-ops.h:62 [inline]
       cfg80211_remove_virtual_intf+0x23f/0x410 net/wireless/util.c:2852
       genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
       genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
       genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210
       netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
       genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
       netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
       netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
       netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
       sock_sendmsg_nosec net/socket.c:730 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:745
       ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
       ___sys_sendmsg net/socket.c:2639 [inline]
       __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&rdev->wiphy.mtx){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
       __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       wiphy_lock include/net/cfg80211.h:5966 [inline]
       cfg80211_netdev_notifier_call+0x308/0x1490 net/wireless/core.c:1524
       notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
       call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
       call_netdevice_notifiers net/core/dev.c:2044 [inline]
       dev_open+0x13a/0x1b0 net/core/dev.c:1513
       team_port_add drivers/net/team/team_core.c:1216 [inline]
       team_add_slave+0x9b3/0x2750 drivers/net/team/team_core.c:1976
       do_set_master net/core/rtnetlink.c:2701 [inline]
       do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907
       __rtnl_newlink net/core/rtnetlink.c:3696 [inline]
       rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
       rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
       netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
       netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
       netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
       netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
       sock_sendmsg_nosec net/socket.c:730 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:745
       ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
       ___sys_sendmsg net/socket.c:2639 [inline]
       __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(team->team_lock_key#7);
                               lock(&rdev->wiphy.mtx);
                               lock(team->team_lock_key#7);
  lock(&rdev->wiphy.mtx);

 *** DEADLOCK ***

2 locks held by syz.3.4018/17170:
 #0: ffffffff8f5e7108 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f5e7108 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x1180 net/core/rtnetlink.c:6632
 #1: ffff88802e624d20 (team->team_lock_key#7){+.+.}-{3:3}, at: team_add_slave+0xad/0x2750 drivers/net/team/team_core.c:1975

stack backtrace:
CPU: 1 PID: 17170 Comm: syz.3.4018 Not tainted 6.10.0-rc5-syzkaller-00198-g9a0c28efeec6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 wiphy_lock include/net/cfg80211.h:5966 [inline]
 cfg80211_netdev_notifier_call+0x308/0x1490 net/wireless/core.c:1524
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
 call_netdevice_notifiers net/core/dev.c:2044 [inline]
 dev_open+0x13a/0x1b0 net/core/dev.c:1513
 team_port_add drivers/net/team/team_core.c:1216 [inline]
 team_add_slave+0x9b3/0x2750 drivers/net/team/team_core.c:1976
 do_set_master net/core/rtnetlink.c:2701 [inline]
 do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907
 __rtnl_newlink net/core/rtnetlink.c:3696 [inline]
 rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
 netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
 ___sys_sendmsg net/socket.c:2639 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3b5b175bd9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3b5bfc9048 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3b5b303f60 RCX: 00007f3b5b175bd9
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00007f3b5b1e4a98 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000004d R14: 00007f3b5b303f60 R15: 00007ffc56eddca8
 </TASK>
net veth1_virt_wifi virt_wifi0: entered promiscuous mode
net veth1_virt_wifi virt_wifi0: entered allmulticast mode
team0: Port device virt_wifi0 added

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/04 10:28 net 9a0c28efeec6 409d975c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in cfg80211_netdev_notifier_call
2024/07/02 09:39 net-next 74d6529b78f7 b294e901 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in cfg80211_netdev_notifier_call
2024/06/29 14:01 net-next 30972a4ea092 757f06b1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in cfg80211_netdev_notifier_call
2024/06/12 17:47 net-next 45403b12c29c 4d75f4f7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in cfg80211_netdev_notifier_call
* Struck through repros no longer work on HEAD.