==================================================================
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 ffff888057310470 by task kworker/u8:2/35
CPU: 0 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
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_state_delete net/xfrm/xfrm_state.c:856 [inline]
xfrm_state_delete_tunnel net/xfrm/xfrm_state.c:3091 [inline]
__xfrm_state_delete+0x87b/0xca0 net/xfrm/xfrm_state.c:837
xfrm_timer_handler+0x18f/0xa00 net/xfrm/xfrm_state.c:716
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x529/0xc60 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:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 5e
RSP: 0018:ffffc90000ab7660 EFLAGS: 00000293
RAX: ffffffff81b44e0b RBX: 1ffff110170e7f61 RCX: ffff888020ee9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000ab77e0 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6
R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff8880b873fb08
R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2653 [inline]
smp_text_poke_batch_finish+0xb44/0x1130 arch/x86/kernel/alternative.c:2925
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855
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+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 5983:
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:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
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+0x208/0x470 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 5976:
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:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4782
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+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 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 ffff888057310440
which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
freed 928-byte region [ffff888057310440, ffff8880573107e0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888057311980 pfn:0x57310
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 ffff888142aa0780 dead000000000122 0000000000000000
raw: ffff888057311980 00000000800f000e 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888142aa0780 dead000000000122 0000000000000000
head: ffff888057311980 00000000800f000e 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00015cc401 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 5983, tgid 5982 (syz.3.4), ts 99575633199, free_ts 99530888472
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:2487 [inline]
allocate_slab+0x8a/0x370 mm/slub.c:2655
new_slab mm/slub.c:2709 [inline]
___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
__slab_alloc mm/slub.c:3981 [inline]
__slab_alloc_node mm/slub.c:4056 [inline]
slab_alloc_node mm/slub.c:4217 [inline]
kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236
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+0x208/0x470 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
page last free pid 5982 tgid 5982 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
stack_depot_save_flags+0x436/0x860 lib/stackdepot.c:727
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_save_track+0x4f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4365 [inline]
__kmalloc_node_noprof+0x276/0x4e0 mm/slub.c:4371
kmalloc_array_node_noprof include/linux/slab.h:1020 [inline]
alloc_slab_obj_exts+0x39/0xa0 mm/slub.c:2028
__memcg_slab_post_alloc_hook+0x31e/0x7f0 mm/memcontrol.c:3174
memcg_slab_post_alloc_hook mm/slub.c:2216 [inline]
slab_post_alloc_hook mm/slub.c:4190 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_noprof+0x2bf/0x3c0 mm/slub.c:4236
alloc_buffer_head+0x2a/0x270 fs/buffer.c:3025
folio_alloc_buffers+0x32d/0x640 fs/buffer.c:935
create_empty_buffers+0x3a/0x530 fs/buffer.c:1691
__block_write_begin_int+0x3b1/0x1900 fs/buffer.c:2126
block_page_mkwrite+0x34f/0x4d0 fs/buffer.c:2639
ext4_page_mkwrite+0xc87/0x1190 fs/ext4/inode.c:6725
do_page_mkwrite+0x14d/0x310 mm/memory.c:3361
do_shared_fault mm/memory.c:5649 [inline]
do_fault mm/memory.c:5711 [inline]
do_pte_missing mm/memory.c:4234 [inline]
handle_pte_fault mm/memory.c:6052 [inline]
__handle_mm_fault+0x1916/0x5440 mm/memory.c:6195
Memory state around the buggy address:
ffff888057310300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888057310380: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888057310400: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
^
ffff888057310480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888057310500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 45 8b 2c 24 mov (%r12),%r13d
4: 44 89 ee mov %r13d,%esi
7: 83 e6 01 and $0x1,%esi
a: 31 ff xor %edi,%edi
c: e8 b6 62 0b 00 call 0xb62c7
11: 41 83 e5 01 and $0x1,%r13d
15: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13
1c: fc ff df
1f: 75 07 jne 0x28
21: e8 61 5e 0b 00 call 0xb5e87
26: eb 38 jmp 0x60
28: f3 90 pause
* 2a: 42 0f b6 04 2b movzbl (%rbx,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 11 jne 0x44
33: 41 f7 04 24 01 00 00 testl $0x1,(%r12)
3a: 00
3b: 74 1e je 0x5b
3d: e8 .byte 0xe8
3e: 45 5e rex.RB pop %r14