syzbot


possible deadlock in __mod_timer

Status: upstream: reported on 2024/04/08 15:59
Reported-by: syzbot+77d73d9fcc34bdd32b00@syzkaller.appspotmail.com
First crash: 24d, last: 5d18h
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in __mod_timer kernel 35 509d 583d 0/26 auto-obsoleted due to no activity on 2023/04/09 11:04
upstream possible deadlock in __mod_timer (2) kernel 1 358d 358d 22/26 fixed on 2023/07/01 16:05

Sample crash report:
------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
5.15.156-syzkaller #0 Not tainted
------------------------------------------------------
syz-fuzzer/3497 is trying to acquire lock:
ffffffff8c7fc358 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138

but task is already holding lock:
ffff8880b9b28098 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x772/0xeb0 kernel/time/timer.c:1043

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&base->lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       lock_timer_base+0x120/0x260 kernel/time/timer.c:946
       __mod_timer+0x1d6/0xeb0 kernel/time/timer.c:1019
       queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1715
       psi_enqueue kernel/sched/stats.h:104 [inline]
       enqueue_task+0x2fe/0x3a0 kernel/sched/core.c:1973
       activate_task kernel/sched/core.c:2005 [inline]
       wake_up_new_task+0x515/0xb60 kernel/sched/core.c:4522
       kernel_clone+0x44e/0x960 kernel/fork.c:2628
       kernel_thread+0x168/0x1e0 kernel/fork.c:2656
       rest_init+0x21/0x330 init/main.c:704
       start_kernel+0x48c/0x540 init/main.c:1138
       secondary_startup_64_no_verify+0xb1/0xbb

-> #2 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368
       raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
       raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
       rq_lock kernel/sched/sched.h:1621 [inline]
       task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11480
       sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4466
       copy_process+0x224a/0x3ef0 kernel/fork.c:2320
       kernel_clone+0x210/0x960 kernel/fork.c:2604
       kernel_thread+0x168/0x1e0 kernel/fork.c:2656
       rest_init+0x21/0x330 init/main.c:704
       start_kernel+0x48c/0x540 init/main.c:1138
       secondary_startup_64_no_verify+0xb1/0xbb

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4030
       up+0x6e/0x90 kernel/locking/semaphore.c:190
       __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:256
       console_unlock+0x1145/0x12b0 kernel/printk/printk.c:2760
       vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       br_set_state+0x35b/0x610 net/bridge/br_stp.c:51
       br_stp_disable_port+0x74/0x1c0 net/bridge/br_stp_if.c:106
       del_nbp+0x176/0xbb0 net/bridge/br_if.c:334
       br_dev_delete+0x68/0x100 net/bridge/br_if.c:377
       default_device_exit_batch+0x2ef/0x3f0 net/core/dev.c:11621
       ops_exit_list net/core/net_namespace.c:174 [inline]
       cleanup_net+0x763/0xb60 net/core/net_namespace.c:596
       process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
       worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
       kthread+0x3f6/0x4f0 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300

-> #0 ((console_sem).lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138
       __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
       console_trylock kernel/printk/printk.c:2575 [inline]
       console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
       vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       report_bug+0x1e5/0x2e0 lib/bug.c:195
       handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
       exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259
       asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:566
       copy_from_user_nofault+0x15c/0x1c0
       bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
       ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
       bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
       bpf_prog_078a3568a35342ea+0x38/0x498
       bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
       __bpf_prog_run include/linux/filter.h:628 [inline]
       bpf_prog_run include/linux/filter.h:635 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
       bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
       trace_timer_start include/trace/events/timer.h:52 [inline]
       enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
       internal_add_timer kernel/time/timer.c:611 [inline]
       __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
       sk_reset_timer+0x1f/0xb0 net/core/sock.c:3136
       tcp_rcv_established+0x135b/0x1e20 net/ipv4/tcp_input.c:5954
       tcp_v4_do_rcv+0x423/0x960 net/ipv4/tcp_ipv4.c:1727
       tcp_v4_rcv+0x2740/0x2d80 net/ipv4/tcp_ipv4.c:2130
       ip_protocol_deliver_rcu+0x381/0x730 net/ipv4/ip_input.c:204
       ip_local_deliver_finish+0x1db/0x320 net/ipv4/ip_input.c:231
       NF_HOOK+0x364/0x410 include/linux/netfilter.h:302
       dst_input include/net/dst.h:453 [inline]
       ip_sublist_rcv_finish net/ipv4/ip_input.c:577 [inline]
       ip_list_rcv_finish net/ipv4/ip_input.c:628 [inline]
       ip_sublist_rcv+0xb0f/0xe50 net/ipv4/ip_input.c:636
       ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:671
       __netif_receive_skb_list_ptype net/core/dev.c:5528 [inline]
       __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5576
       __netif_receive_skb_list net/core/dev.c:5628 [inline]
       netif_receive_skb_list_internal+0x9ed/0xdf0 net/core/dev.c:5719
       gro_normal_list net/core/dev.c:5873 [inline]
       napi_complete_done+0x352/0x820 net/core/dev.c:6611
       virtqueue_napi_complete drivers/net/virtio_net.c:357 [inline]
       virtnet_poll+0xbef/0x1270 drivers/net/virtio_net.c:1592
       __napi_poll+0xc7/0x440 net/core/dev.c:7035
       napi_poll net/core/dev.c:7102 [inline]
       net_rx_action+0x617/0xda0 net/core/dev.c:7192
       __do_softirq+0x3b3/0x93a kernel/softirq.c:558
       invoke_softirq kernel/softirq.c:432 [inline]
       __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
       irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
       common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240
       asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:629
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
       _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
       hrtimer_start_expires include/linux/hrtimer.h:434 [inline]
       hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1966 [inline]
       do_nanosleep+0x164/0x7b0 kernel/time/hrtimer.c:2042
       hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098
       __do_sys_nanosleep kernel/time/hrtimer.c:2133 [inline]
       __se_sys_nanosleep kernel/time/hrtimer.c:2119 [inline]
       __x64_sys_nanosleep+0x265/0x2c0 kernel/time/hrtimer.c:2119
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &rq->__lock --> &base->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&base->lock);
                               lock(&rq->__lock);
                               lock(&base->lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

5 locks held by syz-fuzzer/3497:
 #0: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
 #1: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
 #2: ffff888020a90ca0 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x26aa/0x2d80 net/ipv4/tcp_ipv4.c:2124
 #3: ffff8880b9b28098 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x772/0xeb0 kernel/time/timer.c:1043
 #4: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 1 PID: 3497 Comm: syz-fuzzer Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138
 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
 console_trylock kernel/printk/printk.c:2575 [inline]
 console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
 vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 report_bug+0x1e5/0x2e0 lib/bug.c:195
 handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
 exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259
 asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:566
RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226
Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 db d7 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c4 d7 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff
RSP: 0018:ffffc90000dcfb88 EFLAGS: 00010046
RAX: ffffffff81aa851c RBX: 0000000000000000 RCX: ffff888079ec0000
RDX: 0000000080000104 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff81aa842d R09: fffffbfff1f7ec19
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000020000000
R13: 0000000000000008 R14: 0000000020000000 R15: ffffc90000dcfbe8
 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
 ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
 bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
 bpf_prog_078a3568a35342ea+0x38/0x498
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 trace_timer_start include/trace/events/timer.h:52 [inline]
 enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
 internal_add_timer kernel/time/timer.c:611 [inline]
 __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
 sk_reset_timer+0x1f/0xb0 net/core/sock.c:3136
 tcp_rcv_established+0x135b/0x1e20 net/ipv4/tcp_input.c:5954
 tcp_v4_do_rcv+0x423/0x960 net/ipv4/tcp_ipv4.c:1727
 tcp_v4_rcv+0x2740/0x2d80 net/ipv4/tcp_ipv4.c:2130
 ip_protocol_deliver_rcu+0x381/0x730 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x1db/0x320 net/ipv4/ip_input.c:231
 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302
 dst_input include/net/dst.h:453 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:577 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:628 [inline]
 ip_sublist_rcv+0xb0f/0xe50 net/ipv4/ip_input.c:636
 ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:671
 __netif_receive_skb_list_ptype net/core/dev.c:5528 [inline]
 __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5576
 __netif_receive_skb_list net/core/dev.c:5628 [inline]
 netif_receive_skb_list_internal+0x9ed/0xdf0 net/core/dev.c:5719
 gro_normal_list net/core/dev.c:5873 [inline]
 napi_complete_done+0x352/0x820 net/core/dev.c:6611
 virtqueue_napi_complete drivers/net/virtio_net.c:357 [inline]
 virtnet_poll+0xbef/0x1270 drivers/net/virtio_net.c:1592
 __napi_poll+0xc7/0x440 net/core/dev.c:7035
 napi_poll net/core/dev.c:7102 [inline]
 net_rx_action+0x617/0xda0 net/core/dev.c:7192
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240
 </IRQ>
 <TASK>
 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 05 a3 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 37 45 30 f7 65 8b 05 08 53 db 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc900024e7ba0 EFLAGS: 00000206
RAX: 8865c36dc95e9b00 RBX: 1ffff9200049cf78 RCX: ffffffff913edf03
RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: 0000000000000001
RBP: ffffc900024e7c30 R08: ffffffff8186dd10 R09: ffffed1017365441
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200049cf74 R14: ffffc900024e7bc0 R15: 0000000000000246
 hrtimer_start_expires include/linux/hrtimer.h:434 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1966 [inline]
 do_nanosleep+0x164/0x7b0 kernel/time/hrtimer.c:2042
 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098
 __do_sys_nanosleep kernel/time/hrtimer.c:2133 [inline]
 __se_sys_nanosleep kernel/time/hrtimer.c:2119 [inline]
 __x64_sys_nanosleep+0x265/0x2c0 kernel/time/hrtimer.c:2119
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x472757
Code: 8b 44 24 20 b9 40 42 0f 00 f7 f1 48 89 04 24 b8 e8 03 00 00 f7 e2 48 89 44 24 08 48 89 e7 be 00 00 00 00 b8 23 00 00 00 0f 05 <48> 83 c4 10 5d c3 cc cc cc b8 ba 00 00 00 0f 05 89 44 24 08 c3 cc
RSP: 002b:000000c000069f18 EFLAGS: 00000202 ORIG_RAX: 0000000000000023
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000000472757
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000c000069f18
RBP: 000000c000069f28 R08: 00000000000011d4 R09: 0000000000000010
R10: 00007fff72b90080 R11: 0000000000000202 R12: 000000c000069f18
R13: 000000c0000ed800 R14: 000000c0000064e0 R15: 0000000000000005
 </TASK>
WARNING: CPU: 1 PID: 3497 at mm/maccess.c:226 copy_from_user_nofault+0x15c/0x1c0
Modules linked in:
CPU: 1 PID: 3497 Comm: syz-fuzzer Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226
Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 db d7 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c4 d7 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff
RSP: 0018:ffffc90000dcfb88 EFLAGS: 00010046
RAX: ffffffff81aa851c RBX: 0000000000000000 RCX: ffff888079ec0000
RDX: 0000000080000104 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff81aa842d R09: fffffbfff1f7ec19
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000020000000
R13: 0000000000000008 R14: 0000000020000000 R15: ffffc90000dcfbe8
FS:  000000c000058090(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e722000 CR3: 000000002575d000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
 ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
 bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
 bpf_prog_078a3568a35342ea+0x38/0x498
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 trace_timer_start include/trace/events/timer.h:52 [inline]
 enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
 internal_add_timer kernel/time/timer.c:611 [inline]
 __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
 sk_reset_timer+0x1f/0xb0 net/core/sock.c:3136
 tcp_rcv_established+0x135b/0x1e20 net/ipv4/tcp_input.c:5954
 tcp_v4_do_rcv+0x423/0x960 net/ipv4/tcp_ipv4.c:1727
 tcp_v4_rcv+0x2740/0x2d80 net/ipv4/tcp_ipv4.c:2130
 ip_protocol_deliver_rcu+0x381/0x730 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x1db/0x320 net/ipv4/ip_input.c:231
 NF_HOOK+0x364/0x410 include/linux/netfilter.h:302
 dst_input include/net/dst.h:453 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:577 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:628 [inline]
 ip_sublist_rcv+0xb0f/0xe50 net/ipv4/ip_input.c:636
 ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:671
 __netif_receive_skb_list_ptype net/core/dev.c:5528 [inline]
 __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5576
 __netif_receive_skb_list net/core/dev.c:5628 [inline]
 netif_receive_skb_list_internal+0x9ed/0xdf0 net/core/dev.c:5719
 gro_normal_list net/core/dev.c:5873 [inline]
 napi_complete_done+0x352/0x820 net/core/dev.c:6611
 virtqueue_napi_complete drivers/net/virtio_net.c:357 [inline]
 virtnet_poll+0xbef/0x1270 drivers/net/virtio_net.c:1592
 __napi_poll+0xc7/0x440 net/core/dev.c:7035
 napi_poll net/core/dev.c:7102 [inline]
 net_rx_action+0x617/0xda0 net/core/dev.c:7192
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240
 </IRQ>
 <TASK>
 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 05 a3 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 37 45 30 f7 65 8b 05 08 53 db 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc900024e7ba0 EFLAGS: 00000206
RAX: 8865c36dc95e9b00 RBX: 1ffff9200049cf78 RCX: ffffffff913edf03
RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: 0000000000000001
RBP: ffffc900024e7c30 R08: ffffffff8186dd10 R09: ffffed1017365441
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200049cf74 R14: ffffc900024e7bc0 R15: 0000000000000246
 hrtimer_start_expires include/linux/hrtimer.h:434 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1966 [inline]
 do_nanosleep+0x164/0x7b0 kernel/time/hrtimer.c:2042
 hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098
 __do_sys_nanosleep kernel/time/hrtimer.c:2133 [inline]
 __se_sys_nanosleep kernel/time/hrtimer.c:2119 [inline]
 __x64_sys_nanosleep+0x265/0x2c0 kernel/time/hrtimer.c:2119
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x472757
Code: 8b 44 24 20 b9 40 42 0f 00 f7 f1 48 89 04 24 b8 e8 03 00 00 f7 e2 48 89 44 24 08 48 89 e7 be 00 00 00 00 b8 23 00 00 00 0f 05 <48> 83 c4 10 5d c3 cc cc cc b8 ba 00 00 00 0f 05 89 44 24 08 c3 cc
RSP: 002b:000000c000069f18 EFLAGS: 00000202 ORIG_RAX: 0000000000000023
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000000472757
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000c000069f18
RBP: 000000c000069f28 R08: 00000000000011d4 R09: 0000000000000010
R10: 00007fff72b90080 R11: 0000000000000202 R12: 000000c000069f18
R13: 000000c0000ed800 R14: 000000c0000064e0 R15: 0000000000000005
 </TASK>
----------------
Code disassembly (best guess):
   0:	9c                   	pushf
   1:	8f 44 24 20          	pop    0x20(%rsp)
   5:	42 80 3c 23 00       	cmpb   $0x0,(%rbx,%r12,1)
   a:	74 08                	je     0x14
   c:	4c 89 f7             	mov    %r14,%rdi
   f:	e8 02 05 a3 f7       	call   0xf7a30516
  14:	f6 44 24 21 02       	testb  $0x2,0x21(%rsp)
  19:	75 4e                	jne    0x69
  1b:	41 f7 c7 00 02 00 00 	test   $0x200,%r15d
  22:	74 01                	je     0x25
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 37 45 30 f7       	call   0xf7304566 <-- trapping instruction
  2f:	65 8b 05 08 53 db 75 	mov    %gs:0x75db5308(%rip),%eax        # 0x75db533e
  36:	85 c0                	test   %eax,%eax
  38:	74 3f                	je     0x79
  3a:	48                   	rex.W
  3b:	c7                   	.byte 0xc7
  3c:	04 24                	add    $0x24,%al
  3e:	0e                   	(bad)
  3f:	36                   	ss

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/27 08:06 linux-5.15.y c52b9710c83d 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in __mod_timer
2024/04/18 14:34 linux-5.15.y c52b9710c83d af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in __mod_timer
2024/04/10 19:36 linux-5.15.y cdfd0a7f0139 4320ec32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in __mod_timer
2024/04/08 15:58 linux-5.15.y 9465fef4ae35 53df08b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in __mod_timer
* Struck through repros no longer work on HEAD.