syzbot


possible deadlock in __dev_open

Status: upstream: reported on 2025/03/11 20:10
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+2393ddd2462f9a5f6d79@syzkaller.appspotmail.com
First crash: 4d06h, last: 3h31m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [net?] possible deadlock in __dev_open 1 (2) 2025/03/11 20:26

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc5-syzkaller-01188-g0ea09cbf8350 #0 Not tainted
------------------------------------------------------
syz.1.10412/28074 is trying to acquire lock:
ffff88806fdf0d28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff88806fdf0d28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: netif_set_up net/core/dev.h:143 [inline]
ffff88806fdf0d28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: __dev_open+0x5cb/0x8a0 net/core/dev.c:1651

but task is already holding lock:
ffff88805d864e00 (team->team_lock_key#3){+.+.}-{4:4}, at: team_add_slave+0xb3/0x28a0 drivers/net/team/team_core.c:1988

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (team->team_lock_key#3){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       team_set_mac_address+0x122/0x280 drivers/net/team/team_core.c:1817
       netif_set_mac_address+0x327/0x510 net/core/dev.c:9605
       do_setlink+0xaa6/0x40f0 net/core/rtnetlink.c:3095
       rtnl_changelink net/core/rtnetlink.c:3759 [inline]
       __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
       rtnl_newlink+0x15a6/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       __sys_sendto+0x363/0x4c0 net/socket.c:2178
       __do_sys_sendto net/socket.c:2185 [inline]
       __se_sys_sendto net/socket.c:2181 [inline]
       __x64_sys_sendto+0xde/0x100 net/socket.c:2181
       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

-> #1 (&dev_instance_lock_key#12){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       netdev_lock include/linux/netdevice.h:2731 [inline]
       dev_set_mac_address+0x2a/0x50 net/core/dev_api.c:302
       bond_set_mac_address+0x28e/0x830 drivers/net/bonding/bond_main.c:4903
       netif_set_mac_address+0x327/0x510 net/core/dev.c:9605
       do_setlink+0xaa6/0x40f0 net/core/rtnetlink.c:3095
       rtnl_changelink net/core/rtnetlink.c:3759 [inline]
       __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
       rtnl_newlink+0x15a6/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
       ___sys_sendmsg net/socket.c:2618 [inline]
       __sys_sendmsg+0x269/0x350 net/socket.c:2650
       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 (&dev_instance_lock_key#2){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       netdev_lock include/linux/netdevice.h:2731 [inline]
       netif_set_up net/core/dev.h:143 [inline]
       __dev_open+0x5cb/0x8a0 net/core/dev.c:1651
       netif_open+0xae/0x1b0 net/core/dev.c:1667
       dev_open+0x13e/0x260 net/core/dev_api.c:191
       team_port_add drivers/net/team/team_core.c:1230 [inline]
       team_add_slave+0xabe/0x28a0 drivers/net/team/team_core.c:1989
       do_set_master+0x579/0x730 net/core/rtnetlink.c:2943
       rtnl_newlink_create+0x6e6/0xbd0 net/core/rtnetlink.c:3837
       __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
       rtnl_newlink+0x167a/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
       ___sys_sendmsg net/socket.c:2618 [inline]
       __sys_sendmsg+0x269/0x350 net/socket.c:2650
       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:

Chain exists of:
  &dev_instance_lock_key#2 --> &dev_instance_lock_key#12 --> team->team_lock_key#3

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(team->team_lock_key#3);
                               lock(&dev_instance_lock_key#12);
                               lock(team->team_lock_key#3);
  lock(&dev_instance_lock_key#2);

 *** DEADLOCK ***

3 locks held by syz.1.10412/28074:
 #0: ffffffff903d43a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff903d43a0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff903d43a0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8fed6908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc4c/0x1d90 net/core/rtnetlink.c:4054
 #2: ffff88805d864e00 (team->team_lock_key#3){+.+.}-{4:4}, at: team_add_slave+0xb3/0x28a0 drivers/net/team/team_core.c:1988

stack backtrace:
CPU: 1 UID: 0 PID: 28074 Comm: syz.1.10412 Not tainted 6.14.0-rc5-syzkaller-01188-g0ea09cbf8350 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
 netdev_lock include/linux/netdevice.h:2731 [inline]
 netif_set_up net/core/dev.h:143 [inline]
 __dev_open+0x5cb/0x8a0 net/core/dev.c:1651
 netif_open+0xae/0x1b0 net/core/dev.c:1667
 dev_open+0x13e/0x260 net/core/dev_api.c:191
 team_port_add drivers/net/team/team_core.c:1230 [inline]
 team_add_slave+0xabe/0x28a0 drivers/net/team/team_core.c:1989
 do_set_master+0x579/0x730 net/core/rtnetlink.c:2943
 rtnl_newlink_create+0x6e6/0xbd0 net/core/rtnetlink.c:3837
 __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
 rtnl_newlink+0x167a/0x1d90 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:709 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:724
 ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
 ___sys_sendmsg net/socket.c:2618 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2650
 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: 0033:0x7f78d038d169
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:00007f78d1160038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f78d05a5fa0 RCX: 00007f78d038d169
RDX: 0000000000000000 RSI: 0000400000000000 RDI: 0000000000000003
RBP: 00007f78d040e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f78d05a5fa0 R15: 00007ffd165aa478
 </TASK>
8021q: adding VLAN 0 to HW filter on device bond5
team0: Port device bond5 added

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/12 07:41 net-next 0ea09cbf8350 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/11 23:08 net-next 40587f749df2 f2eee6b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/11 21:49 net-next 40587f749df2 f2eee6b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/11 13:03 net-next 40587f749df2 16256247 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/10 11:51 net-next 8ef890df4031 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/09 21:41 net-next 8ef890df4031 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/08 22:21 net-next 8ef890df4031 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/08 13:40 net-next e2537326e3b6 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
2025/03/08 04:57 net-next e2537326e3b6 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in __dev_open
* Struck through repros no longer work on HEAD.