================================================================== 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 ffff88805667d570 by task syz.3.1318/11062 CPU: 0 UID: 0 PID: 11062 Comm: syz.3.1318 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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_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:strlen+0x29/0x70 lib/string.c:420 Code: 90 f3 0f 1e fa 41 57 41 56 41 54 53 48 c7 c0 ff ff ff ff 49 be 00 00 00 00 00 fc ff df 48 89 fb 49 89 c7 48 89 d8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 75 11 48 ff c3 49 8d 47 01 42 80 7c 3f 01 00 RSP: 0000:ffffc90002e97898 EFLAGS: 00000a03 RAX: 1ffffffff1710e34 RBX: ffffffff8b8871a5 RCX: ffffffff820a7719 RDX: ffffffff820a773f RSI: ffff88807d673138 RDI: ffffffff8b8871a0 RBP: ffffc90002e979b8 R08: ffffea0001a542b7 R09: 1ffffd400034a856 R10: dffffc0000000000 R11: fffff9400034a857 R12: 1ffff920005d2f20 R13: ffffffff820a773f R14: dffffc0000000000 R15: 0000000000000004 __fortify_strlen include/linux/fortify-string.h:268 [inline] trace_event_get_offsets_lock include/trace/events/lock.h:50 [inline] do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0xc2/0x3b0 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x3b2/0x3e0 kernel/locking/lockdep.c:5879 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] do_wp_page+0x6ef/0x5800 mm/memory.c:4008 handle_pte_fault mm/memory.c:6068 [inline] __handle_mm_fault+0x1033/0x5440 mm/memory.c:6195 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364 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: 0033:0x7efef6264b97 Code: 0f 85 11 0e 00 00 4c 89 44 24 28 31 c0 b9 40 42 0f 00 48 89 de ba 81 00 00 00 bf ca 00 00 00 c7 03 01 00 00 00 e8 f9 9f 12 00 <83> 05 0e 32 37 00 01 4c 8b 44 24 28 80 bc 24 e8 00 00 00 00 0f b6 RSP: 002b:00007ffdf963f810 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007efef65d5fa8 RCX: 00007efef638eba9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007efef65d5fa8 RBP: 0000000000000000 R08: 00007ffdf963f6a7 R09: 00000001f963faff R10: 00007efef65d5fa0 R11: 0000000000000246 R12: 00007efef65d5fac R13: 00007efef65d5fa0 R14: 00000000000000a0 R15: 0000000000000003 Allocated by task 10282: 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 5864: 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 ffff88805667d540 which belongs to the cache xfrm_state of size 928 The buggy address is located 48 bytes inside of freed 928-byte region [ffff88805667d540, ffff88805667d8e0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805667d100 pfn:0x5667c 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 ffff88801a5fd780 dead000000000122 0000000000000000 raw: ffff88805667d100 00000000800f0008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a5fd780 dead000000000122 0000000000000000 head: ffff88805667d100 00000000800f0008 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001599f01 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 6050, tgid 6048 (syz.0.19), ts 100787467242, free_ts 29380820667 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 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 1 tgid 1 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 __free_pages mm/page_alloc.c:5260 [inline] free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7091 destroy_args+0x64/0x4a0 mm/debug_vm_pgtable.c:958 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1340 do_one_initcall+0x233/0x820 init/main.c:1269 do_initcall_level+0x104/0x190 init/main.c:1331 do_initcalls+0x59/0xa0 init/main.c:1347 kernel_init_freeable+0x334/0x4b0 init/main.c:1579 kernel_init+0x1d/0x1d0 init/main.c:1469 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88805667d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805667d480: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805667d500: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff88805667d580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805667d600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 90 nop 1: f3 0f 1e fa endbr64 5: 41 57 push %r15 7: 41 56 push %r14 9: 41 54 push %r12 b: 53 push %rbx c: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax 13: 49 be 00 00 00 00 00 movabs $0xdffffc0000000000,%r14 1a: fc ff df 1d: 48 89 fb mov %rdi,%rbx 20: 49 89 c7 mov %rax,%r15 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 75 11 jne 0x44 33: 48 ff c3 inc %rbx 36: 49 8d 47 01 lea 0x1(%r15),%rax 3a: 42 80 7c 3f 01 00 cmpb $0x0,0x1(%rdi,%r15,1)