==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:982 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:560 [inline]
BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0 net/xfrm/xfrm_state.c:830
Write of size 8 at addr ffff888056ac8cf0 by task syz-executor/24296
CPU: 1 UID: 0 PID: 24296 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
__hlist_del include/linux/list.h:982 [inline]
hlist_del_rcu include/linux/rculist.h:560 [inline]
__xfrm_state_delete+0x696/0xca0 net/xfrm/xfrm_state.c:830
xfrm_timer_handler+0x18f/0xa00 net/xfrm/xfrm_state.c:716
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_is_held_type+0x137/0x190 kernel/locking/lockdep.c:5945
Code: 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 05 f9 73 26 07 <48> 3b 44 24 08 75 43 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0000:ffffc9000c817cb8 EFLAGS: 00000206
RAX: caf23b97db95a600 RBX: 0000000000000000 RCX: caf23b97db95a600
RDX: 0000000000000000 RSI: ffffffff8dba9339 RDI: ffffffff8be33d80
RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffffff820a75a1
R10: dffffc0000000000 R11: ffffed1005c379bd R12: 0000000000000246
R13: ffff8880337cda00 R14: ffffffff8e13a1a0 R15: 0000000000000002
lock_is_held include/linux/lockdep.h:249 [inline]
rcu_read_lock_sched_held+0x89/0x100 kernel/rcu/update.c:126
task_css include/linux/cgroup.h:453 [inline]
mem_cgroup_from_task+0x4d/0x120 mm/memcontrol.c:883
count_memcg_events_mm include/linux/memcontrol.h:978 [inline]
count_memcg_event_mm+0x12c/0x260 include/linux/memcontrol.h:987
mm_account_fault mm/memory.c:6229 [inline]
handle_mm_fault+0x50f/0x8e0 mm/memory.c:6390
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f4318b8501d
Code: f9 03 00 00 41 89 c4 85 c0 0f 85 7e 02 00 00 48 8b 05 77 77 d8 00 c7 05 cd 2b 22 00 01 00 00 00 c7 05 63 86 d8 00 00 00 00 00 05 79 77 d8 00 00 00 00 00 48 83 c0 04 48 83 3d f5 b8 21 00 00
RSP: 002b:00007fff4b6a7970 EFLAGS: 00010246
RAX: 0000000000000004 RBX: 0000000000000000 RCX: 00007f4318b8544d
RDX: 0000000000000000 RSI: 0000000000000018 RDI: 000055555825b7e0
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055555825b7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000001789af R15: 00007fff4b6a7b00
Allocated by task 23875:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:330 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4191 [inline]
slab_alloc_node mm/slub.c:4240 [inline]
kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4247
xfrm_state_alloc+0x24/0x2f0 net/xfrm/xfrm_state.c:733
__find_acq_core+0x8a7/0x1c00 net/xfrm/xfrm_state.c:1833
xfrm_find_acq+0x78/0xa0 net/xfrm/xfrm_state.c:2353
xfrm_alloc_userspi+0x6b3/0xc90 net/xfrm/xfrm_user.c:1863
xfrm_user_rcv_msg+0x7a0/0xab0 net/xfrm/xfrm_user.c:3501
netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3523
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:729
____sys_sendmsg+0x505/0x830 net/socket.c:2614
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
__sys_sendmsg net/socket.c:2700 [inline]
__do_sys_sendmsg net/socket.c:2705 [inline]
__se_sys_sendmsg net/socket.c:2703 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5931:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2422 [inline]
slab_free mm/slub.c:4695 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4797
xfrm_state_free net/xfrm/xfrm_state.c:591 [inline]
xfrm_state_gc_destroy net/xfrm/xfrm_state.c:618 [inline]
xfrm_state_gc_task+0x52d/0x6b0 net/xfrm/xfrm_state.c:634
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the object at ffff888056ac8cc0
which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
freed 928-byte region [ffff888056ac8cc0, ffff888056ac9060)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888056ac9100 pfn:0x56ac8
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff8881426bec80 ffffea0001a3e400 0000000000000003
raw: ffff888056ac9100 00000000000f000b 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff8881426bec80 ffffea0001a3e400 0000000000000003
head: ffff888056ac9100 00000000000f000b 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00015ab201 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6159, tgid 6154 (syz.4.49), ts 106336492800, free_ts 106214943406
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:2492 [inline]
allocate_slab+0x8a/0x370 mm/slub.c:2660
new_slab mm/slub.c:2714 [inline]
___slab_alloc+0xbeb/0x1420 mm/slub.c:3901
__slab_alloc mm/slub.c:3992 [inline]
__slab_alloc_node mm/slub.c:4067 [inline]
slab_alloc_node mm/slub.c:4228 [inline]
kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4247
xfrm_state_alloc+0x24/0x2f0 net/xfrm/xfrm_state.c:733
xfrm_state_construct net/xfrm/xfrm_user.c:889 [inline]
xfrm_add_sa+0x17d1/0x4070 net/xfrm/xfrm_user.c:1019
xfrm_user_rcv_msg+0x7a0/0xab0 net/xfrm/xfrm_user.c:3501
netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
xfrm_netlink_rcv+0x79/0x90 net/xfrm/xfrm_user.c:3523
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:729
____sys_sendmsg+0x505/0x830 net/socket.c:2614
page last free pid 6156 tgid 6156 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
discard_slab mm/slub.c:2758 [inline]
__put_partials+0x156/0x1a0 mm/slub.c:3223
put_cpu_partial+0x17c/0x250 mm/slub.c:3298
__slab_free+0x2d5/0x3c0 mm/slub.c:4565
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4191 [inline]
slab_alloc_node mm/slub.c:4240 [inline]
__do_kmalloc_node mm/slub.c:4375 [inline]
__kmalloc_noprof+0x224/0x4f0 mm/slub.c:4388
kmalloc_noprof include/linux/slab.h:909 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
tomoyo_path_perm+0x2b3/0x4b0 security/tomoyo/file.c:831
tomoyo_path_symlink+0xa3/0xe0 security/tomoyo/tomoyo.c:212
security_path_symlink+0x177/0x380 security/security.c:1984
do_symlinkat+0x107/0x3f0 fs/namei.c:4754
__do_sys_symlinkat fs/namei.c:4772 [inline]
__se_sys_symlinkat fs/namei.c:4769 [inline]
__x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4769
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888056ac8b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888056ac8c00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888056ac8c80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
^
ffff888056ac8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888056ac8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 01 75 44 add %esi,0x44(%rbp)
3: 48 c7 04 24 00 00 00 movq $0x0,(%rsp)
a: 00
b: 9c pushf
c: 8f 04 24 pop (%rsp)
f: f7 04 24 00 02 00 00 testl $0x200,(%rsp)
16: 75 4c jne 0x64
18: 41 f7 c4 00 02 00 00 test $0x200,%r12d
1f: 74 01 je 0x22
21: fb sti
22: 65 48 8b 05 f9 73 26 mov %gs:0x72673f9(%rip),%rax # 0x7267423
29: 07
* 2a: 48 3b 44 24 08 cmp 0x8(%rsp),%rax <-- trapping instruction
2f: 75 43 jne 0x74
31: 89 d8 mov %ebx,%eax
33: 48 83 c4 10 add $0x10,%rsp
37: 5b pop %rbx
38: 41 5c pop %r12
3a: 41 5d pop %r13
3c: 41 5e pop %r14
3e: 41 5f pop %r15