==================================================================
BUG: KASAN: slab-use-after-free in timer_is_static_object+0x35/0x80 kernel/time/timer.c:691
Read of size 8 at addr ffff88805a3f9098 by task syz.3.2050/12717
CPU: 0 UID: 0 PID: 12717 Comm: syz.3.2050 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xba/0x230 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
timer_is_static_object+0x35/0x80 kernel/time/timer.c:691
lookup_object_or_alloc lib/debugobjects.c:696 [inline]
debug_object_activate+0x141/0x580 lib/debugobjects.c:837
debug_timer_activate kernel/time/timer.c:793 [inline]
__mod_timer+0xa4f/0xf30 kernel/time/timer.c:1124
call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:208 [inline]
RIP: 0010:perf_sw_event include/linux/perf_event.h:1603 [inline]
RIP: 0010:do_user_addr_fault+0x1ad/0x1340 arch/x86/mm/fault.c:1281
Code: 1b 48 89 de 48 81 e6 00 02 00 00 31 ff e8 db 2a 4e 00 48 81 e3 00 02 00 00 0f 84 4a 0e 00 00 e8 89 0e 56 00 fb 4c 89 7c 24 38 <0f> 1f 44 00 00 e8 d9 25 4e 00 44 89 f6 83 e6 40 31 ff 48 89 74 24
RSP: 0000:ffffc9000206fe68 EFLAGS: 00000202
RAX: 0000000000000383 RBX: 0000000000000200 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8df297ac RDI: ffffffff8c27d080
RBP: dffffc0000000000 R08: ffffffff901198b7 R09: 1ffffffff2023316
R10: dffffc0000000000 R11: fffffbfff2023317 R12: ffffc9000206ff48
R13: 000000110c2a15f5 R14: 0000000000000004 R15: ffff88807fbfbd00
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f1181a71116
Code: ff 48 83 e8 01 48 89 de bf 01 00 00 00 48 c1 e0 0e 48 c1 ee 06 48 01 c8 48 89 d9 81 e6 ff 3f 00 00 48 c1 e9 03 83 e1 07 d3 e7 <40> 84 bc 06 20 20 00 00 0f 85 20 fe ff ff e9 d4 fd ff ff 0f 1f 80
RSP: 002b:00007fffc9f605a0 EFLAGS: 00010202
RAX: 000000110c29c000 RBX: ffffffff846d756e RCX: 0000000000000005
RDX: 000000000000156e RSI: 00000000000035d5 RDI: 0000000000000020
RBP: 0000000000000000 R08: 00007f1181e00000 R09: 00007f1181e02000
R10: 00000000846d7572 R11: 0000000000000000 R12: 00007f1181e16038
R13: 0000000000000024 R14: ffffffff846d7bba R15: 00007f1182945720
Allocated by task 6736:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5380
kmalloc_noprof include/linux/slab.h:950 [inline]
rose_add_node+0x23c/0xf00 net/rose/rose_route.c:85
rose_rt_ioctl+0xd35/0x12a0 net/rose/rose_route.c:748
rose_ioctl+0x3fb/0x8f0 net/rose/af_rose.c:1387
sock_do_ioctl+0x101/0x320 net/socket.c:1247
sock_ioctl+0x5c6/0x7f0 net/socket.c:1368
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 12700:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2685 [inline]
slab_free mm/slub.c:6165 [inline]
kfree+0x1c1/0x630 mm/slub.c:6483
rose_neigh_put include/net/rose.h:166 [inline]
rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183
call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
The buggy address belongs to the object at ffff88805a3f9000
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 152 bytes inside of
freed 512-byte region [ffff88805a3f9000, ffff88805a3f9200)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5a3f8
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fea6c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fea6c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea000168fe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5897, tgid 5897 (udevd), ts 100402746671, free_ts 100375575153
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_slab_page mm/slub.c:3292 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3481
new_slab mm/slub.c:3539 [inline]
refill_objects+0x331/0x3c0 mm/slub.c:7175
refill_sheaf mm/slub.c:2812 [inline]
__pcs_replace_empty_main+0x2e6/0x730 mm/slub.c:4615
alloc_from_pcs mm/slub.c:4717 [inline]
slab_alloc_node mm/slub.c:4851 [inline]
__kmalloc_cache_noprof+0x392/0x660 mm/slub.c:5375
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
kernfs_fop_open+0x397/0xca0 fs/kernfs/file.c:641
do_dentry_open+0x785/0x14e0 fs/open.c:949
vfs_open+0x3b/0x340 fs/open.c:1081
do_open fs/namei.c:4677 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4836
do_file_open+0x23e/0x4a0 fs/namei.c:4865
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5897 tgid 5897 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
__slab_free+0x263/0x2b0 mm/slub.c:5573
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4538 [inline]
slab_alloc_node mm/slub.c:4866 [inline]
__do_kmalloc_node mm/slub.c:5259 [inline]
__kmalloc_noprof+0x316/0x760 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path2_perm+0x2e7/0x760 security/tomoyo/file.c:928
tomoyo_path_rename+0x14e/0x1b0 security/tomoyo/tomoyo.c:300
security_path_rename+0x248/0x460 security/security.c:1519
filename_renameat2+0x4c1/0x9c0 fs/namei.c:6145
__do_sys_rename fs/namei.c:6194 [inline]
__se_sys_rename+0x55/0x2c0 fs/namei.c:6190
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88805a3f8f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88805a3f9000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805a3f9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88805a3f9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88805a3f9180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 1b 48 89 sbb -0x77(%rax),%ecx
3: de 48 81 fimuls -0x7f(%rax)
6: e6 00 out %al,$0x0
8: 02 00 add (%rax),%al
a: 00 31 add %dh,(%rcx)
c: ff ljmp (bad)
d: e8 db 2a 4e 00 call 0x4e2aed
12: 48 81 e3 00 02 00 00 and $0x200,%rbx
19: 0f 84 4a 0e 00 00 je 0xe69
1f: e8 89 0e 56 00 call 0x560ead
24: fb sti
25: 4c 89 7c 24 38 mov %r15,0x38(%rsp)
* 2a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) <-- trapping instruction
2f: e8 d9 25 4e 00 call 0x4e260d
34: 44 89 f6 mov %r14d,%esi
37: 83 e6 40 and $0x40,%esi
3a: 31 ff xor %edi,%edi
3c: 48 rex.W
3d: 89 .byte 0x89
3e: 74 24 je 0x64