==================================================================
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 ffff8881d9b6f1c8 by task syz.1.12/422

CPU: 1 PID: 422 Comm: syz.1.12 Not tainted 5.4.276-syzkaller-00021-g58de09405d1e #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:unmap_single_vma mm/memory.c:1304 [inline]
RIP: 0010:unmap_vmas+0x235/0x4b0 mm/memory.c:1370
Code: 4c 89 e7 e8 1d 3c 09 00 4d 8b 2c 24 4c 89 ef 48 8b 5c 24 10 48 89 de e8 89 58 d9 ff 49 39 dd 0f 83 76 01 00 00 4c 8b 7c 24 18 <4d> 39 fd 4d 0f 47 fd 49 8d 5c 24 08 48 89 d8 48 c1 e8 03 42 80 3c
RSP: 0018:ffff8881ef3577a0 EFLAGS: 00000213 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffff8881f37fee40
RDX: ffff8881f37fee40 RSI: ffffffffffffffff RDI: 00007fb88a3ce000
RBP: ffff8881ef3578b0 R08: ffffffff818ae217 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881ef1684a0
R13: 00007fb88a3ce000 R14: dffffc0000000000 R15: 0000000000000000
 exit_mmap+0x2bc/0x520 mm/mmap.c:3191
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:536 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:846
 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
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fb88b1adf19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb88a42f048 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000003 RBX: 00007fb88b33bf60 RCX: 00007fb88b1adf19
RDX: bfffffffffffffff RSI: 0000000000000000 RDI: 0000000020000180
RBP: 00007fb88b21cbcd R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fb88b33bf60 R15: 00007fffae276cd8

Allocated by task 351:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
 kmalloc include/linux/slab.h:556 [inline]
 kmalloc_array include/linux/slab.h:617 [inline]
 rtnl_newlink+0xfd/0x2060 net/core/rtnetlink.c:3310
 rtnetlink_rcv_msg+0x983/0xc70 net/core/rtnetlink.c:5290
 netlink_rcv_skb+0x1d5/0x420 net/netlink/af_netlink.c:2481
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x936/0xb20 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1915
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 __sys_sendto+0x4f3/0x6c0 net/socket.c:1961
 __do_sys_sendto net/socket.c:1973 [inline]
 __se_sys_sendto net/socket.c:1969 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:1969
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 351:
 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]
 kfree+0x123/0x370 mm/slub.c:4071
 rtnl_newlink+0xfbf/0x2060 net/core/rtnetlink.c:3315
 rtnetlink_rcv_msg+0x983/0xc70 net/core/rtnetlink.c:5290
 netlink_rcv_skb+0x1d5/0x420 net/netlink/af_netlink.c:2481
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x936/0xb20 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1915
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 __sys_sendto+0x4f3/0x6c0 net/socket.c:1961
 __do_sys_sendto net/socket.c:1973 [inline]
 __se_sys_sendto net/socket.c:1969 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:1969
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

The buggy address belongs to the object at ffff8881d9b6f000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 456 bytes inside of
 512-byte region [ffff8881d9b6f000, ffff8881d9b6f200)
The buggy address belongs to the page:
page:ffffea000766db00 refcount:1 mapcount:0 mapping:ffff8881f5c02500 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02500
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL)
 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_slab_page+0x39/0x3c0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x97/0x440 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x2fe/0x490 mm/slub.c:2667
 __slab_alloc+0x62/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 __kmalloc_track_caller+0x16d/0x2b0 mm/slub.c:4449
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0xb4/0x4d0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1080 [inline]
 nlmsg_new include/net/netlink.h:888 [inline]
 netlink_ack+0x2cc/0xa70 net/netlink/af_netlink.c:2415
 netlink_rcv_skb+0x252/0x420 net/netlink/af_netlink.c:2487
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x936/0xb20 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1915
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 __sys_sendto+0x4f3/0x6c0 net/socket.c:1961
 __do_sys_sendto net/socket.c:1973 [inline]
 __se_sys_sendto net/socket.c:1969 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:1969
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
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
 tun_set_iff+0x870/0xdc0 drivers/net/tun.c:2921
 __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

Memory state around the buggy address:
 ffff8881d9b6f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881d9b6f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881d9b6f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff8881d9b6f200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881d9b6f280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1d9939067 P4D 1d9939067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 422 Comm: syz.1.12 Tainted: G    B             5.4.276-syzkaller-00021-g58de09405d1e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010206
RAX: ffffffff8154d48a RBX: 0000000000000100 RCX: ffff8881f37fee40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881d9b6f1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff9500
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881d9b6f1c0
FS:  00007fb88a42f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dd27d000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 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:unmap_single_vma mm/memory.c:1304 [inline]
RIP: 0010:unmap_vmas+0x235/0x4b0 mm/memory.c:1370
Code: 4c 89 e7 e8 1d 3c 09 00 4d 8b 2c 24 4c 89 ef 48 8b 5c 24 10 48 89 de e8 89 58 d9 ff 49 39 dd 0f 83 76 01 00 00 4c 8b 7c 24 18 <4d> 39 fd 4d 0f 47 fd 49 8d 5c 24 08 48 89 d8 48 c1 e8 03 42 80 3c
RSP: 0018:ffff8881ef3577a0 EFLAGS: 00000213 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffff8881f37fee40
RDX: ffff8881f37fee40 RSI: ffffffffffffffff RDI: 00007fb88a3ce000
RBP: ffff8881ef3578b0 R08: ffffffff818ae217 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8881ef1684a0
R13: 00007fb88a3ce000 R14: dffffc0000000000 R15: 0000000000000000
 exit_mmap+0x2bc/0x520 mm/mmap.c:3191
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:536 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:846
 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
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fb88b1adf19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb88a42f048 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000003 RBX: 00007fb88b33bf60 RCX: 00007fb88b1adf19
RDX: bfffffffffffffff RSI: 0000000000000000 RDI: 0000000020000180
RBP: 00007fb88b21cbcd R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fb88b33bf60 R15: 00007fffae276cd8
Modules linked in:
CR2: 0000000000000000
---[ end trace b110539e54e77a0e ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010206
RAX: ffffffff8154d48a RBX: 0000000000000100 RCX: ffff8881f37fee40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881d9b6f1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff9500
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881d9b6f1c0
FS:  00007fb88a42f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dd27d000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	4c 89 e7             	mov    %r12,%rdi
   3:	e8 1d 3c 09 00       	call   0x93c25
   8:	4d 8b 2c 24          	mov    (%r12),%r13
   c:	4c 89 ef             	mov    %r13,%rdi
   f:	48 8b 5c 24 10       	mov    0x10(%rsp),%rbx
  14:	48 89 de             	mov    %rbx,%rsi
  17:	e8 89 58 d9 ff       	call   0xffd958a5
  1c:	49 39 dd             	cmp    %rbx,%r13
  1f:	0f 83 76 01 00 00    	jae    0x19b
  25:	4c 8b 7c 24 18       	mov    0x18(%rsp),%r15
* 2a:	4d 39 fd             	cmp    %r15,%r13 <-- trapping instruction
  2d:	4d 0f 47 fd          	cmova  %r13,%r15
  31:	49 8d 5c 24 08       	lea    0x8(%r12),%rbx
  36:	48 89 d8             	mov    %rbx,%rax
  39:	48 c1 e8 03          	shr    $0x3,%rax
  3d:	42                   	rex.X
  3e:	80                   	.byte 0x80
  3f:	3c                   	.byte 0x3c