KASAN: use-after-free Write in virtrng

==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline]
BUG: KASAN: use-after-free in __refcount_add include/linux/refcount.h:193 [inline]
BUG: KASAN: use-after-free in __refcount_inc include/linux/refcount.h:250 [inline]
BUG: KASAN: use-after-free in refcount_inc include/linux/refcount.h:267 [inline]
BUG: KASAN: use-after-free in get_task_struct include/linux/sched/task.h:113 [inline]
BUG: KASAN: use-after-free in kthread_stop+0x3a/0x3f0 kernel/kthread.c:717
Write of size 4 at addr ffff88811f300028 by task syz.2.5394/17244

CPU: 1 PID: 17244 Comm: syz.2.5394 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_task_struct include/linux/sched/task.h:113 [inline]
 kthread_stop+0x3a/0x3f0 kernel/kthread.c:717
 hwrng_unregister+0x34d/0x4a0 drivers/char/hw_random/core.c:627
 remove_common drivers/char/hw_random/virtio-rng.c:185 [inline]
 virtrng_remove+0xe3/0x210 drivers/char/hw_random/virtio-rng.c:199
 virtio_dev_remove+0xaa/0x1d0 drivers/virtio/virtio.c:332
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 bus_remove_device+0x2f0/0x350 drivers/base/bus.c:531
 device_del+0x63c/0xe50 drivers/base/core.c:3886
 device_unregister+0x15/0x40 drivers/base/core.c:3929
 unregister_virtio_device+0x34/0x60 drivers/virtio/virtio.c:483
 virtio_pci_remove+0x7c/0xf0 drivers/virtio/virtio_pci_common.c:632
 pci_device_remove+0xa4/0x250 drivers/pci/pci-driver.c:483
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 pci_stop_dev drivers/pci/remove.c:22 [inline]
 pci_stop_bus_device+0x10c/0x140 drivers/pci/remove.c:82
 pci_stop_and_remove_bus_device drivers/pci/remove.c:116 [inline]
 pci_stop_and_remove_bus_device_locked+0x1a/0x30 drivers/pci/remove.c:124
 remove_store+0xe2/0x140 drivers/pci/pci-sysfs.c:515
 dev_attr_store+0x6c/0x90 drivers/base/core.c:2389
 sysfs_kf_write+0x137/0x150 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x307/0x470 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ef/0xd00 fs/read_write.c:584
 ksys_write+0x14a/0x260 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcd6599e159
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:00007fcd667c9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcd65c25fa0 RCX: 00007fcd6599e159
RDX: 0000000000000001 RSI: 00002000000004c0 RDI: 0000000000000008
RBP: 00007fcd65a3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcd65c26038 R14: 00007fcd65c25fa0 R15: 00007ffd70d30bd8
 </TASK>

Allocated by task 2:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 kmem_cache_alloc_node+0x179/0x330 mm/slub.c:3429
 alloc_task_struct_node kernel/fork.c:182 [inline]
 dup_task_struct+0x5a/0x900 kernel/fork.c:1078
 copy_process+0x5e7/0x3500 kernel/fork.c:2315
 kernel_clone+0x22f/0x7f0 kernel/fork.c:2903
 kernel_thread+0x103/0x160 kernel/fork.c:2965
 create_kthread kernel/kthread.c:409 [inline]
 kthreadd+0x346/0x480 kernel/kthread.c:760
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 13:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 kmem_cache_free+0x12d/0x300 mm/slub.c:3737
 free_task_struct kernel/fork.c:187 [inline]
 free_task+0x107/0x250 kernel/fork.c:640
 __put_task_struct+0x278/0x3e0 kernel/fork.c:949
 put_task_struct include/linux/sched/task.h:148 [inline]
 delayed_put_task_struct+0x6c/0x1c0 kernel/exit.c:233
 rcu_do_batch+0x52b/0xc30 kernel/rcu/tree.c:2297
 rcu_core+0x486/0xf00 kernel/rcu/tree.c:2557
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq kernel/softirq.c:680 [inline]
 invoke_softirq kernel/softirq.c:497 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1118
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 __call_rcu_common kernel/rcu/tree.c:2807 [inline]
 call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926
 put_task_struct_rcu_user+0x5b/0x90 kernel/exit.c:239
 finish_task_switch+0x346/0x7c0 kernel/sched/core.c:5338
 context_switch kernel/sched/core.c:5428 [inline]
 __schedule+0xcbb/0x1700 kernel/sched/core.c:6762
 schedule+0xbd/0x170 kernel/sched/core.c:6838
 do_nanosleep+0x15a/0x540 kernel/time/hrtimer.c:2048
 hrtimer_nanosleep+0x151/0x340 kernel/time/hrtimer.c:2096
 common_nsleep+0x8f/0xb0 kernel/time/posix-timers.c:1268
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1309 [inline]
 __se_sys_clock_nanosleep+0x31c/0x3b0 kernel/time/posix-timers.c:1286
 __x64_sys_clock_nanosleep+0x9b/0xb0 kernel/time/posix-timers.c:1286
 x64_sys_call+0x186/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:231
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88811f300000
 which belongs to the cache task_struct of size 4928
The buggy address is located 40 bytes inside of
 4928-byte region [ffff88811f300000, ffff88811f301340)

The buggy address belongs to the physical page:
page:ffffea00047cc000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11f300
head:ffffea00047cc000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff8881001eac00
raw: 0000000000000000 0000000000060006 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 16964, tgid 16964 (syz.2.5319), ts 1407075002142, free_ts 1406997685429
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680
 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587
 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3e0 mm/slub.c:2020
 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 kmem_cache_alloc_node+0x1ba/0x330 mm/slub.c:3429
 alloc_task_struct_node kernel/fork.c:182 [inline]
 dup_task_struct+0x5a/0x900 kernel/fork.c:1078
 copy_process+0x5e7/0x3500 kernel/fork.c:2315
 kernel_clone+0x22f/0x7f0 kernel/fork.c:2903
 __do_sys_clone3 kernel/fork.c:3204 [inline]
 __se_sys_clone3 kernel/fork.c:3188 [inline]
 __x64_sys_clone3+0x2ce/0x360 kernel/fork.c:3188
 x64_sys_call+0x4ce/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:436
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1581 [inline]
 free_pcp_prepare mm/page_alloc.c:1655 [inline]
 free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622
 free_unref_page+0x93/0x530 mm/page_alloc.c:3720
 free_the_page+0x13/0x20 mm/page_alloc.c:863
 page_frag_free+0x10a/0x120 mm/page_alloc.c:6160
 skb_free_frag include/linux/skbuff.h:3315 [inline]
 skb_free_head net/core/skbuff.c:763 [inline]
 skb_release_data+0x70d/0x8a0 net/core/skbuff.c:794
 skb_release_all net/core/skbuff.c:859 [inline]
 __kfree_skb net/core/skbuff.c:873 [inline]
 skb_attempt_defer_free+0x10e/0x420 net/core/skbuff.c:6704
 tcp_eat_recv_skb net/ipv4/tcp.c:1647 [inline]
 tcp_recvmsg_locked+0x14ea/0x23c0 net/ipv4/tcp.c:2656
 tcp_recvmsg+0x21a/0x820 net/ipv4/tcp.c:2702
 inet_recvmsg+0x141/0x480 net/ipv4/af_inet.c:875
 sock_recvmsg_nosec net/socket.c:1021 [inline]
 sock_recvmsg net/socket.c:1039 [inline]
 sock_read_iter+0x2ee/0x3b0 net/socket.c:1112
 call_read_iter include/linux/fs.h:2276 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x46e/0x930 fs/read_write.c:470
 ksys_read+0x14a/0x260 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x7b/0x90 fs/read_write.c:621
 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88811f2fff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88811f2fff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88811f300000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88811f300080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811f300100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 17244 at lib/refcount.c:25 refcount_warn_saturate+0x104/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 1 PID: 17244 Comm: syz.2.5394 Tainted: G    B              syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:refcount_warn_saturate+0x104/0x1a0 lib/refcount.c:25
Code: 05 01 48 c7 c7 00 15 ca 85 e8 b8 c8 d8 fe 0f 0b eb df e8 ef 42 08 ff c6 05 ff 81 26 05 01 48 c7 c7 40 14 ca 85 e8 9c c8 d8 fe <0f> 0b eb c3 e8 d3 42 08 ff c6 05 e4 81 26 05 01 48 c7 c7 a0 14 ca
RSP: 0018:ffffc900041c7700 EFLAGS: 00010246
RAX: ab46e2667b409300 RBX: 0000000000000002 RCX: 0000000000080000
RDX: ffffc90005611000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900041c7710 R08: ffffc900041c72e7 R09: 1ffff92000838e5c
R10: dffffc0000000000 R11: fffff52000838e5d R12: ffffffff8745c188
R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000
FS:  00007fcd667c96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34f1eff8 CR3: 000000012daf5000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_add include/linux/refcount.h:-1 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_task_struct include/linux/sched/task.h:113 [inline]
 kthread_stop+0x1c1/0x3f0 kernel/kthread.c:717
 hwrng_unregister+0x34d/0x4a0 drivers/char/hw_random/core.c:627
 remove_common drivers/char/hw_random/virtio-rng.c:185 [inline]
 virtrng_remove+0xe3/0x210 drivers/char/hw_random/virtio-rng.c:199
 virtio_dev_remove+0xaa/0x1d0 drivers/virtio/virtio.c:332
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 bus_remove_device+0x2f0/0x350 drivers/base/bus.c:531
 device_del+0x63c/0xe50 drivers/base/core.c:3886
 device_unregister+0x15/0x40 drivers/base/core.c:3929
 unregister_virtio_device+0x34/0x60 drivers/virtio/virtio.c:483
 virtio_pci_remove+0x7c/0xf0 drivers/virtio/virtio_pci_common.c:632
 pci_device_remove+0xa4/0x250 drivers/pci/pci-driver.c:483
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 pci_stop_dev drivers/pci/remove.c:22 [inline]
 pci_stop_bus_device+0x10c/0x140 drivers/pci/remove.c:82
 pci_stop_and_remove_bus_device drivers/pci/remove.c:116 [inline]
 pci_stop_and_remove_bus_device_locked+0x1a/0x30 drivers/pci/remove.c:124
 remove_store+0xe2/0x140 drivers/pci/pci-sysfs.c:515
 dev_attr_store+0x6c/0x90 drivers/base/core.c:2389
 sysfs_kf_write+0x137/0x150 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x307/0x470 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ef/0xd00 fs/read_write.c:584
 ksys_write+0x14a/0x260 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcd6599e159
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:00007fcd667c9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcd65c25fa0 RCX: 00007fcd6599e159
RDX: 0000000000000001 RSI: 00002000000004c0 RDI: 0000000000000008
RBP: 00007fcd65a3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcd65c26038 R14: 00007fcd65c25fa0 R15: 00007ffd70d30bd8
 </TASK>
---[ end trace 0000000000000000 ]---
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 116bb7067 P4D 116bb7067 PUD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 17244 Comm: syz.2.5394 Tainted: G    B   W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:arch_set_bit include/linux/instrumented.h:87 [inline]
RIP: 0010:set_bit include/asm-generic/bitops/instrumented-atomic.h:29 [inline]
RIP: 0010:kthread_stop+0xe3/0x3f0 kernel/kthread.c:719
Code: 06 00 00 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 11 cc 6c 00 4c 8b bb d8 06 00 00 4c 89 ff be 08 00 00 00 e8 9d ce 6c 00 <f0> 41 80 0f 02 48 89 df e8 e0 fa ff ff 48 89 df be 08 00 00 00 e8
RSP: 0018:ffffc900041c7720 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88811f300000 RCX: ffffffff814a2963
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffc900041c7748 R08: 0000000000000000 R09: 1ffff92000838e5c
R10: dffffc0000000000 R11: fffff52000838e5d R12: ffffffff8745c188
R13: dffffc0000000000 R14: ffff88811f300028 R15: 0000000000000000
FS:  00007fcd667c96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000012daf5000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 hwrng_unregister+0x34d/0x4a0 drivers/char/hw_random/core.c:627
 remove_common drivers/char/hw_random/virtio-rng.c:185 [inline]
 virtrng_remove+0xe3/0x210 drivers/char/hw_random/virtio-rng.c:199
 virtio_dev_remove+0xaa/0x1d0 drivers/virtio/virtio.c:332
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 bus_remove_device+0x2f0/0x350 drivers/base/bus.c:531
 device_del+0x63c/0xe50 drivers/base/core.c:3886
 device_unregister+0x15/0x40 drivers/base/core.c:3929
 unregister_virtio_device+0x34/0x60 drivers/virtio/virtio.c:483
 virtio_pci_remove+0x7c/0xf0 drivers/virtio/virtio_pci_common.c:632
 pci_device_remove+0xa4/0x250 drivers/pci/pci-driver.c:483
 device_remove drivers/base/dd.c:548 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x486/0x7e0 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 pci_stop_dev drivers/pci/remove.c:22 [inline]
 pci_stop_bus_device+0x10c/0x140 drivers/pci/remove.c:82
 pci_stop_and_remove_bus_device drivers/pci/remove.c:116 [inline]
 pci_stop_and_remove_bus_device_locked+0x1a/0x30 drivers/pci/remove.c:124
 remove_store+0xe2/0x140 drivers/pci/pci-sysfs.c:515
 dev_attr_store+0x6c/0x90 drivers/base/core.c:2389
 sysfs_kf_write+0x137/0x150 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x307/0x470 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x5ef/0xd00 fs/read_write.c:584
 ksys_write+0x14a/0x260 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcd6599e159
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:00007fcd667c9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcd65c25fa0 RCX: 00007fcd6599e159
RDX: 0000000000000001 RSI: 00002000000004c0 RDI: 0000000000000008
RBP: 00007fcd65a3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcd65c26038 R14: 00007fcd65c25fa0 R15: 00007ffd70d30bd8
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_set_bit include/linux/instrumented.h:87 [inline]
RIP: 0010:set_bit include/asm-generic/bitops/instrumented-atomic.h:29 [inline]
RIP: 0010:kthread_stop+0xe3/0x3f0 kernel/kthread.c:719
Code: 06 00 00 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 11 cc 6c 00 4c 8b bb d8 06 00 00 4c 89 ff be 08 00 00 00 e8 9d ce 6c 00 <f0> 41 80 0f 02 48 89 df e8 e0 fa ff ff 48 89 df be 08 00 00 00 e8
RSP: 0018:ffffc900041c7720 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88811f300000 RCX: ffffffff814a2963
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffc900041c7748 R08: 0000000000000000 R09: 1ffff92000838e5c
R10: dffffc0000000000 R11: fffff52000838e5d R12: ffffffff8745c188
R13: dffffc0000000000 R14: ffff88811f300028 R15: 0000000000000000
FS:  00007fcd667c96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000012daf5000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	48 89 f8             	mov    %rdi,%rax
   5:	48 c1 e8 03          	shr    $0x3,%rax
   9:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   e:	74 05                	je     0x15
  10:	e8 11 cc 6c 00       	call   0x6ccc26
  15:	4c 8b bb d8 06 00 00 	mov    0x6d8(%rbx),%r15
  1c:	4c 89 ff             	mov    %r15,%rdi
  1f:	be 08 00 00 00       	mov    $0x8,%esi
  24:	e8 9d ce 6c 00       	call   0x6ccec6
* 29:	f0 41 80 0f 02       	lock orb $0x2,(%r15) <-- trapping instruction
  2e:	48 89 df             	mov    %rbx,%rdi
  31:	e8 e0 fa ff ff       	call   0xfffffb16
  36:	48 89 df             	mov    %rbx,%rdi
  39:	be 08 00 00 00       	mov    $0x8,%esi
  3e:	e8                   	.byte 0xe8