[syzbot] [net?] INFO: task hung in genl_rcv_msg (4)

syzbot
2024-10-02T23:00:29Z

Hello,

syzbot found the following issue on:

HEAD commit: e7ed34365879 Merge tag 'mailbox-v6.12' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12067d9f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=c9af6222e6678002
dashboard link: https://syzkaller.appspot.com/bug?extid=85d0bec020d805014a3a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/caf1c2797333/disk-e7ed3436.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/94f2d55f85c6/vmlinux-e7ed3436.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ee9ab0ca36d2/bzImage-e7ed3436.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+85d0bec020d805014a3a@syzkaller.appspotmail.com

INFO: task syz.5.230:6022 blocked for more than 143 seconds.
Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.230 state:D stack:27136 pid:6022 tgid:6019 ppid:5225 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
genl_lock net/netlink/genetlink.c:35 [inline]
genl_op_lock net/netlink/genetlink.c:60 [inline]
genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x223/0x270 net/socket.c:744
____sys_sendmsg+0x52a/0x7e0 net/socket.c:2602
___sys_sendmsg net/socket.c:2656 [inline]
__sys_sendmsg+0x292/0x380 net/socket.c:2685
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: 0033:0x7f435577dff9
RSP: 002b:00007f43564ab038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f4355936058 RCX: 00007f435577dff9
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007f43557f0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f4355936058 R15: 00007ffe2fc70808
</TASK>
INFO: task syz.1.234:6050 blocked for more than 144 seconds.
Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.234 state:D stack:27392 pid:6050 tgid:6046 ppid:5226 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
genl_lock net/netlink/genetlink.c:35 [inline]
genl_op_lock net/netlink/genetlink.c:60 [inline]
genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x223/0x270 net/socket.c:744
__sys_sendto+0x39b/0x4f0 net/socket.c:2209
__do_sys_sendto net/socket.c:2221 [inline]
__se_sys_sendto net/socket.c:2217 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2217
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: 0033:0x7fc9aab7fe8c
RSP: 002b:00007fc9ab94aec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc9ab94afc0 RCX: 00007fc9aab7fe8c
RDX: 0000000000000020 RSI: 00007fc9ab94b010 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fc9ab94af14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fc9ab94af68 R14: 00007fc9ab94b010 R15: 0000000000000000
</TASK>
INFO: task syz.3.238:6057 blocked for more than 145 seconds.
Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.238 state:D stack:27360 pid:6057 tgid:6056 ppid:5238 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
genl_lock net/netlink/genetlink.c:35 [inline]
genl_op_lock net/netlink/genetlink.c:60 [inline]
genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x223/0x270 net/socket.c:744
__sys_sendto+0x39b/0x4f0 net/socket.c:2209
__do_sys_sendto net/socket.c:2221 [inline]
__se_sys_sendto net/socket.c:2217 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2217
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: 0033:0x7fc88857fe8c
RSP: 002b:00007fc889291ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fc889291fc0 RCX: 00007fc88857fe8c
RDX: 0000000000000024 RSI: 00007fc889292010 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fc889291f14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fc889291f68 R14: 00007fc889292010 R15: 0000000000000000
</TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:1/12:
#0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90000117d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90000117d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580
#3: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:173 [inline]
#3: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x30/0x100 net/sched/act_gate.c:659
1 lock held by khungtaskd/30:
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
2 locks held by kworker/u8:2/35:
3 locks held by kworker/u8:3/52:
#0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc90000bc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc90000bc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
2 locks held by dhcpcd/4891:
#0: ffff8880324c96c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: netlink_dump+0xcb/0xd80 net/netlink/af_netlink.c:2271
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6505
2 locks held by getty/4979:
#0: ffff88803249a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
6 locks held by kworker/0:6/5298:
3 locks held by kworker/1:7/5403:
#0: ffff88801ac79948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
#0: ffff88801ac79948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
#1: ffffc9000322fd00 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
#1: ffffc9000322fd00 ((crda_timeout).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
#2: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: crda_timeout_work+0x15/0x50 net/wireless/reg.c:540
8 locks held by syz-executor/5663:
#0: ffff8880325d2420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline]
#0: ffff8880325d2420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679
#1: ffff88807883dc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325
#2: ffff88802778c5a8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326
#3: ffffffff8f56f788 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
#4: ffff88805afb90e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#4: ffff88805afb90e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
#4: ffff88805afb90e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293
#5: ffff88805afba250 (&devlink->lock_key#6){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672
#6: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773
#7: ffffffff8e7d1dd0 (cpu_hotplug_lock){++++}-{0:0}, at: flush_all_backlogs net/core/dev.c:6021 [inline]
#7: ffffffff8e7d1dd0 (cpu_hotplug_lock){++++}-{0:0}, at: unregister_netdevice_many_notify+0x5ea/0x1da0 net/core/dev.c:11380
3 locks held by syz.5.230/6020:
#0: ffffffff8fd37470 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
#2: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_register_hw+0x312b/0x3e10 net/mac80211/main.c:1584
2 locks held by syz.5.230/6022:
#0: ffffffff8fd37470 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
2 locks held by syz.1.234/6050:
#0: ffffffff8fd37470 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
2 locks held by syz.3.238/6057:
#0: ffffffff8fd37470 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8fd37328 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x121/0xec0 net/netlink/genetlink.c:1209
1 lock held by syz.0.239/6060:
#0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
1 lock held by syz-executor/6106:
#0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643
2 locks held by syz-executor/6112:
#0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x720 net/ipv4/ip_tunnel.c:1159
2 locks held by syz-executor/6117:
#0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3885
2 locks held by syz-executor/6120:
#0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3885
2 locks held by syz-executor/6123:
#0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3885
2 locks held by syz-executor/6126:
#0: ffffffff8fcc4c10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:490
#1: ffffffff8fcd1708 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3885

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xff4/0x1040 kernel/hung_task.c:379
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5298 Comm: kworker/0:6 Not tainted 6.11.0-syzkaller-12113-ge7ed34365879 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:_raw_spin_unlock_irqrestore+0x67/0x140 kernel/locking/spinlock.c:193
Code: c7 04 24 b3 8a b5 41 48 c7 44 24 08 2a f1 08 8e 48 c7 44 24 10 20 03 cf 8b 49 89 e5 49 c1 ed 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 <4b> 89 44 25 00 48 83 c7 18 48 8b 75 08 e8 77 67 a1 f5 48 89 df e8
RSP: 0018:ffffc90000006f20 EFLAGS: 00000016
RAX: f3f3f300f1f1f1f1 RBX: ffffffff9a6128c8 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 0000000000000246 RDI: ffffffff9a6128c8
RBP: ffffc90000006fb0 R08: 0000000000000003 R09: fffff52000000dd4
R10: dffffc0000000000 R11: fffff52000000dd4 R12: dffffc0000000000
R13: 1ffff92000000de4 R14: ffffc90000006f40 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3251bff8 CR3: 000000000e734000 CR4: 0000000000350ef0
Call Trace:
<NMI>
</NMI>
<IRQ>
__debug_check_no_obj_freed lib/debugobjects.c:998 [inline]
debug_check_no_obj_freed+0x561/0x580 lib/debugobjects.c:1019
slab_free_hook mm/slub.c:2274 [inline]
slab_free mm/slub.c:4580 [inline]
kmem_cache_free+0x11f/0x420 mm/slub.c:4682
nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60
nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
nft_do_chain+0x4af/0x1da0 net/netfilter/nf_tables_core.c:288
nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:626
nf_hook include/linux/netfilter.h:269 [inline]
NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312
NF_HOOK+0x3a6/0x450 include/linux/netfilter.h:314
__netif_receive_skb_one_core net/core/dev.c:5662 [inline]
__netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775
process_backlog+0x662/0x15b0 net/core/dev.c:6107
__napi_poll+0xcd/0x490 net/core/dev.c:6771
napi_poll net/core/dev.c:6840 [inline]
net_rx_action+0x89b/0x1240 net/core/dev.c:6962
handle_softirqs+0x2c7/0x980 kernel/softirq.c:554
do_softirq+0x11b/0x1e0 kernel/softirq.c:455
</IRQ>
<TASK>
__local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
spin_unlock_bh include/linux/spinlock.h:396 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

---
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