==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:791 [inline]
BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:824 [inline]
BUG: KASAN: use-after-free in expire_timers kernel/time/timer.c:1482 [inline]
BUG: KASAN: use-after-free in __run_timers+0x7be/0xbe0 kernel/time/timer.c:1817
Write of size 8 at addr ffff8881ee1171c8 by task syz.0.1261/5178

CPU: 1 PID: 5178 Comm: syz.0.1261 Tainted: G        W         5.4.290-syzkaller-00002-g41adfeb3d639 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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_del include/linux/list.h:791 [inline]
 detach_timer kernel/time/timer.c:824 [inline]
 expire_timers kernel/time/timer.c:1482 [inline]
 __run_timers+0x7be/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/0x490 arch/x86/kernel/apic/apic.c:1161
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:vm_normal_page+0xaa/0x1d0 mm/memory.c:659
Code: e8 eb af d9 ff 49 39 dd 0f 87 90 00 00 00 e8 3d ae d9 ff 49 c1 e5 06 48 bb 00 00 00 00 00 ea ff ff 4c 01 eb 48 89 d8 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 48 bd 00 00 00 00 00 fc ff df 49 8d 9f 90
RSP: 0018:ffff8881e399f578 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: ffffea000766b1c0 RBX: 0000000000000000 RCX: ffff8881f37caf40
RDX: 0000000000000000 RSI: 000000000023ffff RDI: 00000000001d9ac7
RBP: ffff8881e399f701 R08: ffffffff818a9cb5 R09: ffffed103e6f95e9
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 000000000766b1c0 R14: 00007fe3dfa01000 R15: ffff8881d6043128
 zap_pte_range mm/memory.c:1078 [inline]
 zap_pmd_range mm/memory.c:1222 [inline]
 zap_pud_range mm/memory.c:1251 [inline]
 zap_p4d_range mm/memory.c:1272 [inline]
 unmap_page_range+0xc00/0x2620 mm/memory.c:1293
 unmap_single_vma mm/memory.c:1338 [inline]
 unmap_vmas+0x355/0x4b0 mm/memory.c:1370
 exit_mmap+0x2bc/0x520 mm/mmap.c:3191
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:538 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:848
 do_group_exit+0x138/0x300 kernel/exit.c:984
 get_signal+0xdb1/0x1440 kernel/signal.c:2738
 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
RIP: 0033:0x7fe3e0c57169
Code: Bad RIP value.
RSP: 002b:00007fe3df29f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: 000000000000000b RBX: 00007fe3e0e7f080 RCX: 00007fe3e0c57169
RDX: 0000000000200002 RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007fe3e0cd9a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe3e0e7f080 R15: 00007ffd5fc35cd8

The buggy address belongs to the page:
page:ffffea0007b845c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea0007b845c8 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:9629
 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:1776
 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:9488
 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:2738
 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
 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:346

Memory state around the buggy address:
 ffff8881ee117080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881ee117100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881ee117180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881ee117200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881ee117280: 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: 5178 Comm: syz.0.1261 Tainted: G    B   W         5.4.290-syzkaller-00002-g41adfeb3d639 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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 63 51 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 a5 66 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 32 51 3f 00 4d 89 65 00 eb 05 e8 77
RSP: 0018:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103dc22e39 RCX: dffffc0000000000
RDX: 0000000000000102 RSI: 0000000000000008 RDI: ffff8881ee1171c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103dc22e38 R15: ffff8881ee1171c8
FS:  00007fe3df29f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3e0c5713f CR3: 00000001ee9eb000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
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/0x490 arch/x86/kernel/apic/apic.c:1161
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:vm_normal_page+0xaa/0x1d0 mm/memory.c:659
Code: e8 eb af d9 ff 49 39 dd 0f 87 90 00 00 00 e8 3d ae d9 ff 49 c1 e5 06 48 bb 00 00 00 00 00 ea ff ff 4c 01 eb 48 89 d8 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 48 bd 00 00 00 00 00 fc ff df 49 8d 9f 90
RSP: 0018:ffff8881e399f578 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: ffffea000766b1c0 RBX: 0000000000000000 RCX: ffff8881f37caf40
RDX: 0000000000000000 RSI: 000000000023ffff RDI: 00000000001d9ac7
RBP: ffff8881e399f701 R08: ffffffff818a9cb5 R09: ffffed103e6f95e9
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 000000000766b1c0 R14: 00007fe3dfa01000 R15: ffff8881d6043128
 zap_pte_range mm/memory.c:1078 [inline]
 zap_pmd_range mm/memory.c:1222 [inline]
 zap_pud_range mm/memory.c:1251 [inline]
 zap_p4d_range mm/memory.c:1272 [inline]
 unmap_page_range+0xc00/0x2620 mm/memory.c:1293
 unmap_single_vma mm/memory.c:1338 [inline]
 unmap_vmas+0x355/0x4b0 mm/memory.c:1370
 exit_mmap+0x2bc/0x520 mm/mmap.c:3191
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:538 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:848
 do_group_exit+0x138/0x300 kernel/exit.c:984
 get_signal+0xdb1/0x1440 kernel/signal.c:2738
 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
RIP: 0033:0x7fe3e0c57169
Code: Bad RIP value.
RSP: 002b:00007fe3df29f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: 000000000000000b RBX: 00007fe3e0e7f080 RCX: 00007fe3e0c57169
RDX: 0000000000200002 RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007fe3e0cd9a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe3e0e7f080 R15: 00007ffd5fc35cd8
Modules linked in:
---[ end trace 82c49ea76ee6d52a ]---
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 63 51 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 a5 66 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 32 51 3f 00 4d 89 65 00 eb 05 e8 77
RSP: 0018:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103dc22e39 RCX: dffffc0000000000
RDX: 0000000000000102 RSI: 0000000000000008 RDI: ffff8881ee1171c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103dc22e38 R15: ffff8881ee1171c8
FS:  00007fe3df29f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3e0c5713f CR3: 00000001ee9eb000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
   0:	e8 eb af d9 ff       	call   0xffd9aff0
   5:	49 39 dd             	cmp    %rbx,%r13
   8:	0f 87 90 00 00 00    	ja     0x9e
   e:	e8 3d ae d9 ff       	call   0xffd9ae50
  13:	49 c1 e5 06          	shl    $0x6,%r13
  17:	48 bb 00 00 00 00 00 	movabs $0xffffea0000000000,%rbx
  1e:	ea ff ff
  21:	4c 01 eb             	add    %r13,%rbx
  24:	48 89 d8             	mov    %rbx,%rax
  27:	5b                   	pop    %rbx
  28:	41 5c                	pop    %r12
* 2a:	41 5d                	pop    %r13 <-- trapping instruction
  2c:	41 5e                	pop    %r14
  2e:	41 5f                	pop    %r15
  30:	5d                   	pop    %rbp
  31:	c3                   	ret
  32:	48 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%rbp
  39:	fc ff df
  3c:	49                   	rex.WB
  3d:	8d                   	.byte 0x8d
  3e:	9f                   	lahf
  3f:	90                   	nop