==================================================================
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 ffff88803380d130 by task kworker/u8:21/14615

CPU: 1 UID: 0 PID: 14615 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound nsim_dev_trap_report_work
Call Trace:
 <IRQ>
 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+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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 7b 21 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9001e42f3d8 EFLAGS: 00000206
RAX: 45ad7f3b651deb00 RBX: 0000000000000000 RCX: 45ad7f3b651deb00
RDX: 0000000000000000 RSI: ffffffff8dba8220 RDI: ffffffff8be33880
RBP: ffffffff8172c195 R08: 0000000000000000 R09: ffffffff8172c195
R10: ffffc9001e42f598 R11: ffffffff81ac3ae0 R12: 0000000000000002
R13: ffffffff8e139f20 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 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_node_noprof+0x1bb/0x3c0 mm/slub.c:4292
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659
 alloc_skb include/linux/skbuff.h:1336 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:763 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
 nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:866
 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+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 18351:
 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+0x82f/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 43:
 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+0x3fc/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 ffff88803380d100
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff88803380d100, ffff88803380d4a0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3380c
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 ffff88801af0f780 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800f000f 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801af0f780 dead000000000122 0000000000000000
head: 0000000000000000 00000000800f000f 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000ce0301 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 18190, tgid 18185 (syz.4.3401), ts 427737059879, free_ts 423774307373
 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_find+0x37d4/0x5400 net/xfrm/xfrm_state.c:1513
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2522 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2573 [inline]
 xfrm_resolve_and_create_bundle+0x768/0x2f80 net/xfrm/xfrm_policy.c:2871
 xfrm_lookup_with_ifid+0x2a7/0x1a70 net/xfrm/xfrm_policy.c:3205
 xfrm_lookup net/xfrm/xfrm_policy.c:3336 [inline]
 xfrm_lookup_route+0x3c/0x1c0 net/xfrm/xfrm_policy.c:3347
 udp_sendmsg+0x142e/0x2170 net/ipv4/udp.c:1450
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:729
 ____sys_sendmsg+0x52d/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
page last free pid 24 tgid 24 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]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4292
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659
 alloc_skb include/linux/skbuff.h:1336 [inline]
 mld_newpack+0x13c/0xc40 net/ipv6/mcast.c:1780
 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1891
 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2030
 mld_send_cr net/ipv6/mcast.c:2153 [inline]
 mld_ifc_work+0x6ed/0xd60 net/ipv6/mcast.c:2698
 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

Memory state around the buggy address:
 ffff88803380d000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
 ffff88803380d080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803380d100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88803380d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803380d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	9c                   	pushf
   5:	8f 44 24 30          	pop    0x30(%rsp)
   9:	f7 44 24 30 00 02 00 	testl  $0x200,0x30(%rsp)
  10:	00
  11:	0f 85 cd 00 00 00    	jne    0xe4
  17:	f7 44 24 08 00 02 00 	testl  $0x200,0x8(%rsp)
  1e:	00
  1f:	74 01                	je     0x22
  21:	fb                   	sti
  22:	65 48 8b 05 7b 21 03 	mov    %gs:0x1103217b(%rip),%rax        # 0x110321a5
  29:	11
* 2a:	48 3b 44 24 58       	cmp    0x58(%rsp),%rax <-- trapping instruction
  2f:	0f 85 f2 00 00 00    	jne    0x127
  35:	48 83 c4 60          	add    $0x60,%rsp
  39:	5b                   	pop    %rbx
  3a:	41 5c                	pop    %r12
  3c:	41 5d                	pop    %r13
  3e:	41 5e                	pop    %r14