==================================================================
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 ffff8881e19d71c8 by task swapper/1/0
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.290-syzkaller-00002-g41adfeb3d639 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__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/0x490 arch/x86/kernel/apic/apic.c:1161
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
RIP: 0010:default_idle+0x1f/0x30 arch/x86/kernel/process.c:573
Code: 90 90 90 90 90 90 90 90 90 90 90 e8 8b af da fd bf 01 00 00 00 89 c6 e8 ef 93 d1 fc 0f 1f 44 00 00 0f 00 2d 23 a3 4d 00 fb f4 6c af da fd bf ff ff ff ff 89 c6 e9 d0 93 d1 fc 41 57 41 56 53
RSP: 0018:ffff8881f5df7d78 EFLAGS: 000002d2 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff8881f5dc1f80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffff8881f5df7e80 R08: ffffffff8231cd01 R09: ffffed103ebb83f1
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff864c4d68
R13: ffff8881f5dc1f80 R14: 1ffff1103ebb83f0 R15: 0000000000000001
default_idle_call kernel/sched/idle.c:94 [inline]
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x248/0x660 kernel/sched/idle.c:264
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:356
start_secondary+0x3a5/0x460 arch/x86/kernel/smpboot.c:277
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
The buggy address belongs to the page:
page:ffffea00078675c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea0007867588 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
tun_set_iff+0x870/0xdc0 drivers/net/tun.c:2924
__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
Memory state around the buggy address:
ffff8881e19d7080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e19d7100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e19d7180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881e19d7200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e19d7280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
9: 90 nop
a: 90 nop
b: e8 8b af da fd call 0xfddaaf9b
10: bf 01 00 00 00 mov $0x1,%edi
15: 89 c6 mov %eax,%esi
17: e8 ef 93 d1 fc call 0xfcd1940b
1c: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
21: 0f 00 2d 23 a3 4d 00 verw 0x4da323(%rip) # 0x4da34b
28: fb sti
29: f4 hlt
* 2a: e8 6c af da fd call 0xfddaaf9b <-- trapping instruction
2f: bf ff ff ff ff mov $0xffffffff,%edi
34: 89 c6 mov %eax,%esi
36: e9 d0 93 d1 fc jmp 0xfcd1940b
3b: 41 57 push %r15
3d: 41 56 push %r14
3f: 53 push %rbx