==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:906 [inline]
BUG: KASAN: use-after-free in hlist_del_init_rcu include/linux/rculist.h:184 [inline]
BUG: KASAN: use-after-free in __xfrm_state_delete+0x3db/0x940 net/xfrm/xfrm_state.c:700
Write of size 8 at addr ffff8880771c1190 by task swapper/0/0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:420
kasan_report+0x10b/0x140 mm/kasan/report.c:524
__hlist_del include/linux/list.h:906 [inline]
hlist_del_init_rcu include/linux/rculist.h:184 [inline]
__xfrm_state_delete+0x3db/0x940 net/xfrm/xfrm_state.c:700
xfrm_timer_handler+0x10b/0x970 net/xfrm/xfrm_state.c:631
__run_hrtimer kernel/time/hrtimer.c:1751 [inline]
__hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815
hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832
handle_softirqs+0x291/0x910 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 e7 7f 92 f7 e9 44 ff ff ff e8 0d 0b f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d d7 5b 65 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8d807da8 EFLAGS: 000002c2
RAX: 60b12446e0136200 RBX: ffffffff8a415177 RCX: 60b12446e0136200
RDX: 0000000000000001 RSI: ffffffff8aac1cc0 RDI: ffffffff8afe72a0
RBP: ffffffff8d807ec8 R08: ffff8880b8c357db R09: 1ffff11017186afb
R10: dffffc0000000000 R11: ffffed1017186afc R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8d8bc740 R15: 1ffffffff1b00fc0
default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3a2/0x680 kernel/sched/idle.c:323
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:422
rest_init+0x2dc/0x300 init/main.c:706
arch_call_rest_init+0xa/0xa init/main.c:865
start_kernel+0x480/0x50d init/main.c:1113
secondary_startup_64_no_verify+0xcf/0xdb
Allocated by task 4351:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:936 [inline]
__kmalloc+0xb3/0x240 mm/slab_common.c:949
xfrm_hash_resize+0x84/0xff0 net/xfrm/xfrm_state.c:156
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Freed by task 4988:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1735 [inline]
slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1761
slab_free mm/slub.c:3694 [inline]
__kmem_cache_free+0xb6/0x200 mm/slub.c:3707
xfrm_hash_resize+0xdce/0xff0 net/xfrm/xfrm_state.c:198
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
The buggy address belongs to the object at ffff8880771c1000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 400 bytes inside of
2048-byte region [ffff8880771c1000, ffff8880771c1800)
The buggy address belongs to the physical page:
page:ffffea0001dc7000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x771c0
head:ffffea0001dc7000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea00006fa600 dead000000000002 ffff888018442000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4276, tgid 4276 (syz-executor), ts 64303000659, free_ts 64243292096
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560
prep_new_page mm/page_alloc.c:2567 [inline]
get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358
__alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658
alloc_slab_page+0x5d/0x180 mm/slub.c:1805
allocate_slab mm/slub.c:1950 [inline]
new_slab+0x87/0x2d0 mm/slub.c:2003
___slab_alloc+0xbc5/0x1240 mm/slub.c:3161
__slab_alloc mm/slub.c:3247 [inline]
slab_alloc_node mm/slub.c:3332 [inline]
__kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3405
__do_kmalloc_node mm/slab_common.c:935 [inline]
__kmalloc+0xa3/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
kzalloc include/linux/slab.h:699 [inline]
ops_init+0x8a/0x5e0 net/core/net_namespace.c:128
setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336
copy_net_ns+0x33e/0x5b0 net/core/net_namespace.c:508
create_new_namespaces+0x3ce/0x700 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226
ksys_unshare+0x4f6/0x8e0 kernel/fork.c:3289
__do_sys_unshare kernel/fork.c:3363 [inline]
__se_sys_unshare kernel/fork.c:3361 [inline]
__x64_sys_unshare+0x34/0x40 kernel/fork.c:3361
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1487 [inline]
free_pcp_prepare mm/page_alloc.c:1537 [inline]
free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509
free_slab mm/slub.c:2042 [inline]
discard_slab mm/slub.c:2048 [inline]
__unfreeze_partials+0x188/0x1e0 mm/slub.c:2598
put_cpu_partial+0x17c/0x250 mm/slub.c:2674
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x490 mm/slab.h:742
slab_alloc_node mm/slub.c:3366 [inline]
__kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3405
__do_kmalloc_node mm/slab_common.c:935 [inline]
__kmalloc+0xa3/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
tomoyo_realpath_from_path+0xe2/0x5c0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x26f/0x610 security/tomoyo/file.c:822
security_inode_getattr+0xcf/0x120 security/security.c:1365
vfs_getattr+0x26/0x3a0 fs/stat.c:158
vfs_fstat fs/stat.c:183 [inline]
__do_sys_newfstat fs/stat.c:447 [inline]
__se_sys_newfstat fs/stat.c:444 [inline]
__x64_sys_newfstat+0x13d/0x220 fs/stat.c:444
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
Memory state around the buggy address:
ffff8880771c1080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880771c1100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880771c1180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880771c1200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880771c1280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 48 89 df mov %rbx,%rdi
3: e8 e7 7f 92 f7 call 0xf7927fef
8: e9 44 ff ff ff jmp 0xffffff51
d: e8 0d 0b f6 ff call 0xfff60b1f
12: 00 00 add %al,(%rax)
14: cc int3
15: cc int3
16: 00 00 add %al,(%rax)
18: cc int3
19: cc int3
1a: 00 00 add %al,(%rax)
1c: cc int3
1d: cc int3
1e: 00 66 90 add %ah,-0x70(%rsi)
21: 0f 00 2d d7 5b 65 00 verw 0x655bd7(%rip) # 0x655bff
28: fb sti
29: f4 hlt
* 2a: c3 ret <-- trapping instruction
2b: 0f 1f 40 00 nopl 0x0(%rax)
2f: 41 57 push %r15
31: 41 56 push %r14
33: 53 push %rbx
34: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14
3b: fc ff df
3e: 65 gs
3f: 48 rex.W