==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e404f1c8 by task udevd/535

CPU: 1 PID: 535 Comm: udevd Not tainted 5.4.283-syzkaller-04984-ge6ac8beecb16 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 hlist_add_head include/linux/list.h:814 [inline]
 enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
 __internal_add_timer kernel/time/timer.c:554 [inline]
 internal_add_timer+0x240/0x430 kernel/time/timer.c:604
 __mod_timer+0x6f1/0x13e0 kernel/time/timer.c:1065
 call_timer_fn+0x36/0x390 kernel/time/timer.c:1448
 expire_timers kernel/time/timer.c:1493 [inline]
 __run_timers+0x879/0xbe0 kernel/time/timer.c:1817
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830
 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x195/0x1c0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:539 [inline]
 smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1149
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:207 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x70 kernel/kcov.c:274
Code: 77 cf 89 f8 89 f6 48 c7 44 0a 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 90 4c 8b 04 24 <65> 48 8b 05 e4 53 9e 7e 65 8b 0d e9 53 9e 7e f7 c1 00 01 1f 00 74
RSP: 0018:ffff8881eaf67940 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 0000000000000109 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff819ee974 R09: ffffffff819eb4b2
R10: ffff8881eacd8000 R11: 0000000000000002 R12: ffff8881eaf67c80
R13: 1ffff1103d5ecf79 R14: ffff8881edfd3330 R15: ffff8881eaf67bc8
 step_into+0x3f4/0x5d0 fs/namei.c:1849
 do_last fs/namei.c:3530 [inline]
 path_openat+0xf48/0x34b0 fs/namei.c:3683
 do_filp_open+0x20b/0x450 fs/namei.c:3713
 do_sys_open+0x39c/0x810 fs/open.c:1123
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f3b6e49b9a4
Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe2438bc10 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00005594d1058cf0 RCX: 00007f3b6e49b9a4
RDX: 0000000000080000 RSI: 00005594d1037e90 RDI: 00000000ffffff9c
RBP: 00005594d1037e90 R08: 00005594d1037e90 R09: 0000000000200000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000
R13: 0000000000000703 R14: 0000000000000000 R15: 0000000000000001

The buggy address belongs to the page:
page:ffffea00079013c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffffff07900101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x146dc0(GFP_USER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__GFP_ZERO)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
 __alloc_pages include/linux/gfp.h:503 [inline]
 __alloc_pages_node include/linux/gfp.h:516 [inline]
 alloc_pages_node include/linux/gfp.h:530 [inline]
 kmalloc_order mm/slab_common.c:1342 [inline]
 kmalloc_order_trace+0x2a/0x100 mm/slab_common.c:1358
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kvmalloc_node+0x7e/0xf0 mm/util.c:596
 kvmalloc include/linux/mm.h:761 [inline]
 kvzalloc include/linux/mm.h:769 [inline]
 alloc_netdev_mqs+0x85/0xc70 net/core/dev.c:9610
 tun_set_iff+0x51f/0xdc0 drivers/net/tun.c:2893
 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3187
 do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
 ksys_ioctl fs/ioctl.c:742 [inline]
 __do_sys_ioctl fs/ioctl.c:749 [inline]
 __se_sys_ioctl fs/ioctl.c:747 [inline]
 __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4955 [inline]
 __free_pages+0x91/0x140 mm/page_alloc.c:4961
 device_release+0x6b/0x190 drivers/base/core.c:1777
 kobject_cleanup lib/kobject.c:716 [inline]
 kobject_release lib/kobject.c:747 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1e6/0x2f0 lib/kobject.c:764
 netdev_run_todo+0xc44/0xdf0 net/core/dev.c:9469
 tun_detach drivers/net/tun.c:766 [inline]
 tun_chr_close+0xc1/0x130 drivers/net/tun.c:3563
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcaf/0x2bc0 kernel/exit.c:861
 do_group_exit+0x138/0x300 kernel/exit.c:984
 get_signal+0xdb1/0x1440 kernel/signal.c:2735
 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159
 prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881e404f080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e404f100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e404f180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881e404f200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e404f280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 535 Comm: udevd Tainted: G    B             5.4.283-syzkaller-04984-ge6ac8beecb16 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__hlist_del include/linux/list.h:791 [inline]
RIP: 0010:detach_timer kernel/time/timer.c:824 [inline]
RIP: 0010:expire_timers kernel/time/timer.c:1482 [inline]
RIP: 0010:__run_timers+0x7b0/0xbe0 kernel/time/timer.c:1817
Code: 89 e7 e8 23 4f 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 a5 65 0f 00 49 83 c5 08 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 f2 4e 3f 00 4d 89 65 00 eb 05 e8 77
RSP: 0000:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103c809e39 RCX: dffffc0000000000
RDX: 0000000080000101 RSI: 0000000000000008 RDI: ffff8881e404f1c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103c809e38 R15: ffff8881e404f1c8
FS:  00007f3b6e370c80(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe70047248 CR3: 00000001ebb53000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830
 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x195/0x1c0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:539 [inline]
 smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1149
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0033:0x7f3b6e44ba76
Code: 83 ec 38 c7 47 08 00 00 00 00 31 db 49 87 1f 48 85 db 0f 84 2d 01 00 00 f6 c3 0f 74 09 48 8d 3d bb e9 0e 00 eb 1d 48 8b 7b 08 <89> f8 c1 e8 04 83 e8 02 49 8d 44 c6 10 49 39 c7 74 0c 48 8d 3d d3
RSP: 002b:00007ffe24390110 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 00005594d1024e70 RCX: 00007f3b6e49b5f4
RDX: 00007ffe24390240 RSI: 0000000000000000 RDI: 0000000000000031
RBP: 00007f3b6e576aa0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000001000 R11: 0000000000000206 R12: 00007f3b6e576b00
R13: 0000000000001000 R14: 00007f3b6e576aa0 R15: 00007f3b6e576ab8
Modules linked in:
---[ end trace e7e781aeb1e9a7b9 ]---
RIP: 0010:__hlist_del include/linux/list.h:791 [inline]
RIP: 0010:detach_timer kernel/time/timer.c:824 [inline]
RIP: 0010:expire_timers kernel/time/timer.c:1482 [inline]
RIP: 0010:__run_timers+0x7b0/0xbe0 kernel/time/timer.c:1817
Code: 89 e7 e8 23 4f 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 a5 65 0f 00 49 83 c5 08 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 f2 4e 3f 00 4d 89 65 00 eb 05 e8 77
RSP: 0000:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103c809e39 RCX: dffffc0000000000
RDX: 0000000080000101 RSI: 0000000000000008 RDI: ffff8881e404f1c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103c809e38 R15: ffff8881e404f1c8
FS:  00007f3b6e370c80(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe70047248 CR3: 00000001ebb53000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	77 cf                	ja     0xffffffd1
   2:	89 f8                	mov    %edi,%eax
   4:	89 f6                	mov    %esi,%esi
   6:	48 c7 44 0a 08 03 00 	movq   $0x3,0x8(%rdx,%rcx,1)
   d:	00 00
   f:	48 89 44 0a 10       	mov    %rax,0x10(%rdx,%rcx,1)
  14:	48 89 74 0a 18       	mov    %rsi,0x18(%rdx,%rcx,1)
  19:	4c 89 44 0a 20       	mov    %r8,0x20(%rdx,%rcx,1)
  1e:	49 ff c1             	inc    %r9
  21:	4c 89 09             	mov    %r9,(%rcx)
  24:	c3                   	ret
  25:	90                   	nop
  26:	4c 8b 04 24          	mov    (%rsp),%r8
* 2a:	65 48 8b 05 e4 53 9e 	mov    %gs:0x7e9e53e4(%rip),%rax        # 0x7e9e5416 <-- trapping instruction
  31:	7e
  32:	65 8b 0d e9 53 9e 7e 	mov    %gs:0x7e9e53e9(%rip),%ecx        # 0x7e9e5422
  39:	f7 c1 00 01 1f 00    	test   $0x1f0100,%ecx
  3f:	74                   	.byte 0x74