==================================================================
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 ffff8881e30131c8 by task syz.2.2310/6028

CPU: 1 PID: 6028 Comm: syz.2.2310 Not tainted 5.4.276-syzkaller-00020-g4275fce9fe94 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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:__orc_find arch/x86/kernel/unwind_orc.c:46 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:175 [inline]
RIP: 0010:unwind_next_frame+0x62c/0x1ea0 arch/x86/kernel/unwind_orc.c:438
Code: 00 00 fc ff df 0f b6 04 08 84 c0 75 27 48 63 03 48 01 d8 48 8d 4b 04 4c 39 e0 4c 0f 46 e9 48 8d 43 fc 4c 0f 47 f8 4c 0f 46 f3 <4d> 39 fd 76 a8 e9 ec fc ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c cd
RSP: 0018:ffff8881ea91ebc0 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13
RAX: ffffffff864e7680 RBX: ffffffff864e7684 RCX: ffffffff864e7688
RDX: ffffffff864e7684 RSI: ffffffff8677fe18 RDI: ffffffff812fbc9c
RBP: ffff8881ea91eeb0 R08: 0000000000000007 R09: ffff8881ea91ef10
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff81006a1f
R13: ffffffff864e7688 R14: ffffffff864e7684 R15: ffffffff864e7684
 arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1c0 kernel/stacktrace.c:123
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
 free_buffer_head+0x42/0xa0 fs/buffer.c:3367
 try_to_free_buffers+0x343/0x3d0 fs/buffer.c:3282
 jbd2_journal_try_to_free_buffers+0x3ce/0x440 fs/jbd2/transaction.c:2132
 do_invalidatepage mm/truncate.c:163 [inline]
 truncate_cleanup_page+0xe3/0x1e0 mm/truncate.c:182
 truncate_inode_pages_range+0x8b5/0x1a20 mm/truncate.c:362
 ext4_evict_inode+0x9ce/0x1ac0 fs/ext4/inode.c:253
 evict+0x29b/0x6a0 fs/inode.c:575
 __dentry_kill+0x429/0x630 fs/dcache.c:579
 dentry_kill+0xb8/0x280 fs/dcache.c:673
 dput+0x3c/0x80 fs/dcache.c:860
 __fput+0x443/0x680 fs/file_table.c:294
 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:859
 do_group_exit+0x138/0x300 kernel/exit.c:982
 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
 ret_from_intr+0x1c/0x1c
RIP: 0033:0xfb86
Code: Bad RIP value.
RSP: 002b:0000000020000308 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f9d44a3cfa0 RCX: 00007f9d448aeb99
RDX: 0000000020000340 RSI: 0000000020000300 RDI: 0000000010201000
RBP: 00007f9d4492f77e R08: 00000000200003c0 R09: 00000000200003c0
R10: 0000000020000380 R11: 0000000000000206 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9d44a3cfa0 R15: 00007ffe979073c8

The buggy address belongs to the page:
page:ffffea00078c04c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea00078c0488 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:2890
 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3184
 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:9469
 tun_detach drivers/net/tun.c:766 [inline]
 tun_chr_close+0xc1/0x130 drivers/net/tun.c:3560
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x190/0x1a0 arch/x86/entry/common.c:163
 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:
 ffff8881e3013080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e3013100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e3013180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881e3013200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e3013280: 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: 6028 Comm: syz.2.2310 Tainted: G    B             5.4.276-syzkaller-00020-g4275fce9fe94 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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 93 4e 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 e5 68 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 62 4e 3f 00 4d 89 65 00 eb 05 e8 b7
RSP: 0018:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103c602639 RCX: dffffc0000000000
RDX: 0000000080000102 RSI: 0000000000000008 RDI: ffff8881e30131c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103c602638 R15: ffff8881e30131c8
FS:  00007f9d43b306c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001dcc7f000 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: 0010:unwind_next_frame+0x163d/0x1ea0 arch/x86/kernel/unwind_orc.c:579
Code: 89 e8 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 ec 07 00 00 49 0f bf 04 24 49 01 c7 48 8b 3c 24 4c 89 fe 4c 89 f2 eb 43 4d 8d 75 02 <49> 83 c5 03 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 dc 07
RSP: 0018:ffff8881ea91ebc0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff8881ea91eec0 RCX: 0000000000000000
RDX: ffff8881ea91ee40 RSI: 0000000000000001 RDI: ffff8881ea91ef20
RBP: ffff8881ea91eeb0 R08: dffffc0000000000 R09: ffff8881ea91ef10
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff0cf962b
R13: ffffffff867cb15a R14: ffffffff867cb15c R15: dffffc0000000000
 arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1c0 kernel/stacktrace.c:123
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
 free_buffer_head+0x42/0xa0 fs/buffer.c:3367
 try_to_free_buffers+0x343/0x3d0 fs/buffer.c:3282
 jbd2_journal_try_to_free_buffers+0x3ce/0x440 fs/jbd2/transaction.c:2132
 do_invalidatepage mm/truncate.c:163 [inline]
 truncate_cleanup_page+0xe3/0x1e0 mm/truncate.c:182
 truncate_inode_pages_range+0x8b5/0x1a20 mm/truncate.c:362
 ext4_evict_inode+0x9ce/0x1ac0 fs/ext4/inode.c:253
 evict+0x29b/0x6a0 fs/inode.c:575
 __dentry_kill+0x429/0x630 fs/dcache.c:579
 dentry_kill+0xb8/0x280 fs/dcache.c:673
 dput+0x3c/0x80 fs/dcache.c:860
 __fput+0x443/0x680 fs/file_table.c:294
 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:859
 do_group_exit+0x138/0x300 kernel/exit.c:982
 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
 ret_from_intr+0x1c/0x1c
RIP: 0033:0xfb86
Code: Bad RIP value.
RSP: 002b:0000000020000308 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f9d44a3cfa0 RCX: 00007f9d448aeb99
RDX: 0000000020000340 RSI: 0000000020000300 RDI: 0000000010201000
RBP: 00007f9d4492f77e R08: 00000000200003c0 R09: 00000000200003c0
R10: 0000000020000380 R11: 0000000000000206 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9d44a3cfa0 R15: 00007ffe979073c8
Modules linked in:
---[ end trace c664bd61a05a44ce ]---
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 93 4e 3f 00 4d 89 2c 24 4d 85 ed 74 2e e8 e5 68 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 62 4e 3f 00 4d 89 65 00 eb 05 e8 b7
RSP: 0018:ffff8881f6f09d60 EFLAGS: 00010802
RAX: 1bd5a00000000025 RBX: 1ffff1103c602639 RCX: dffffc0000000000
RDX: 0000000080000102 RSI: 0000000000000008 RDI: ffff8881e30131c8
RBP: ffff8881f6f09ec8 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881f6f09e20
R13: dead00000000012a R14: 1ffff1103c602638 R15: ffff8881e30131c8
FS:  00007f9d43b306c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000fb5c CR3: 00000001dcc7f000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	df 0f                	fisttps (%rdi)
   2:	b6 04                	mov    $0x4,%dh
   4:	08 84 c0 75 27 48 63 	or     %al,0x63482775(%rax,%rax,8)
   b:	03 48 01             	add    0x1(%rax),%ecx
   e:	d8 48 8d             	fmuls  -0x73(%rax)
  11:	4b 04 4c             	rex.WXB add $0x4c,%al
  14:	39 e0                	cmp    %esp,%eax
  16:	4c 0f 46 e9          	cmovbe %rcx,%r13
  1a:	48 8d 43 fc          	lea    -0x4(%rbx),%rax
  1e:	4c 0f 47 f8          	cmova  %rax,%r15
  22:	4c 0f 46 f3          	cmovbe %rbx,%r14
* 26:	4d 39 fd             	cmp    %r15,%r13 <-- trapping instruction
  29:	76 a8                	jbe    0xffffffd3
  2b:	e9 ec fc ff ff       	jmp    0xfffffd1c
  30:	89 d9                	mov    %ebx,%ecx
  32:	80 e1 07             	and    $0x7,%cl
  35:	80 c1 03             	add    $0x3,%cl
  38:	38 c1                	cmp    %al,%cl
  3a:	7c cd                	jl     0x9