================================================================== 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 ffff88807df988b0 by task syz.8.1086/10352 CPU: 1 UID: 0 PID: 10352 Comm: syz.8.1086 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+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:spin_unlock include/linux/spinlock.h:391 [inline] RIP: 0010:__text_poke+0x7ac/0xa10 arch/x86/kernel/alternative.c:2528 Code: 00 4d 85 f6 75 16 e8 43 56 58 00 eb 15 e8 3c 56 58 00 e8 07 f2 11 0a 4d 85 f6 74 ea e8 2d 56 58 00 fb 48 8b bc 24 e0 00 00 00 7f 87 14 0a e8 aa f8 11 0a 89 c3 31 ff 89 c6 e8 4f 5a 58 00 85 RSP: 0018:ffffc9000b6a7480 EFLAGS: 00000287 RAX: ffffffff81675623 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffffc9001d905000 RSI: 000000000000238d RDI: ffff88801a47b060 RBP: ffffc9000b6a75d0 R08: ffffffff8fa38037 R09: 1ffffffff1f47006 R10: dffffc0000000000 R11: fffffbfff1f47007 R12: dffffc0000000000 R13: ffff88801a47c558 R14: 0000000000000200 R15: ffffffff8b7b1079 text_poke arch/x86/kernel/alternative.c:2552 [inline] smp_text_poke_batch_finish+0x90a/0x1130 arch/x86/kernel/alternative.c:2885 __static_call_transform+0x4eb/0x750 arch/x86/kernel/static_call.c:111 arch_static_call_transform+0x98/0xc0 arch/x86/kernel/static_call.c:-1 __static_call_update+0x3c3/0x5d0 kernel/static_call_inline.c:209 tracepoint_update_call kernel/tracepoint.c:271 [inline] tracepoint_add_func+0x91e/0xa10 kernel/tracepoint.c:312 tracepoint_probe_register_prio kernel/tracepoint.c:464 [inline] tracepoint_probe_register+0x5d/0x90 kernel/tracepoint.c:484 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x4de/0x9d0 kernel/trace/trace_event_perf.c:202 perf_trace_init+0x23d/0x2d0 kernel/trace/trace_event_perf.c:226 perf_tp_event_init+0x8d/0x120 kernel/events/core.c:10852 perf_try_init_event+0x17c/0x870 kernel/events/core.c:12581 perf_init_event kernel/events/core.c:12679 [inline] perf_event_alloc+0x133e/0x2be0 kernel/events/core.c:12954 __do_sys_perf_event_open kernel/events/core.c:13472 [inline] __se_sys_perf_event_open+0x772/0x1d70 kernel/events/core.c:13353 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 RIP: 0033:0x7f17a078eba9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f17a16d0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f17a09d6090 RCX: 00007f17a078eba9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007f17a0811e19 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f17a09d6128 R14: 00007f17a09d6090 R15: 00007fff0e59f9b8 Allocated by task 9654: 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+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 5908: 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 ffff88807df98880 which belongs to the cache xfrm_state of size 928 The buggy address is located 48 bytes inside of freed 928-byte region [ffff88807df98880, ffff88807df98c20) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807df98000 pfn:0x7df98 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 ffff888142eeb3c0 dead000000000122 0000000000000000 raw: ffff88807df98000 00000000800f000c 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff888142eeb3c0 dead000000000122 0000000000000000 head: ffff88807df98000 00000000800f000c 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001f7e601 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 6209, tgid 6208 (syz.2.61), ts 114613334423, free_ts 114424875956 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 pfkey_msg2xfrm_state net/key/af_key.c:1122 [inline] pfkey_add+0x6e4/0x2e00 net/key/af_key.c:1504 pfkey_process net/key/af_key.c:2848 [inline] pfkey_sendmsg+0xbfe/0x1090 net/key/af_key.c:3699 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 page last free pid 6203 tgid 6200 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 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_node_noprof+0x1bb/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1336 [inline] nlmsg_new include/net/netlink.h:1055 [inline] br_info_notify+0x105/0x260 net/bridge/br_netlink.c:647 br_ifinfo_notify net/bridge/br_netlink.c:670 [inline] br_setlink+0x33e/0x800 net/bridge/br_netlink.c:1138 rtnl_bridge_setlink+0x5b2/0x7d0 net/core/rtnetlink.c:5522 rtnetlink_rcv_msg+0x779/0xb70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 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 Memory state around the buggy address: ffff88807df98780: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88807df98800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807df98880: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807df98900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807df98980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 4d 85 add %cl,-0x7b(%rbp) 3: f6 75 16 divb 0x16(%rbp) 6: e8 43 56 58 00 call 0x58564e b: eb 15 jmp 0x22 d: e8 3c 56 58 00 call 0x58564e 12: e8 07 f2 11 0a call 0xa11f21e 17: 4d 85 f6 test %r14,%r14 1a: 74 ea je 0x6 1c: e8 2d 56 58 00 call 0x58564e 21: fb sti 22: 48 8b bc 24 e0 00 00 mov 0xe0(%rsp),%rdi 29: 00 * 2a: e8 7f 87 14 0a call 0xa1487ae <-- trapping instruction 2f: e8 aa f8 11 0a call 0xa11f8de 34: 89 c3 mov %eax,%ebx 36: 31 ff xor %edi,%edi 38: 89 c6 mov %eax,%esi 3a: e8 4f 5a 58 00 call 0x585a8e 3f: 85 .byte 0x85