================================================================== 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 ffff88804f46ccf0 by task syz.8.1300/11164 CPU: 0 UID: 0 PID: 11164 Comm: syz.8.1300 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:memcg_page_state_unit mm/memcontrol.c:1391 [inline] RIP: 0010:memcg_state_val_in_pages mm/memcontrol.c:672 [inline] RIP: 0010:mod_memcg_state+0xbb/0x2f0 mm/memcontrol.c:701 Code: 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ef e8 7c 7e f8 ff 4c 63 f5 4d 8b 6d 00 41 80 fc 29 0f 83 7c 01 00 00 65 4f 01 74 e5 18 <83> fb 36 48 8b 3c 24 0f 87 e4 00 00 00 89 d8 48 b9 60 00 00 00 00 RSP: 0018:ffffc90003d9f548 EFLAGS: 00000206 RAX: 1ffff11008b1a276 RBX: 0000000000000035 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: ffffffff8b984720 RDI: ffffffff8be34480 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff822c658a R10: dffffc0000000000 R11: ffffed1003a81fa4 R12: 0000000000000025 R13: 0000607ed9e00d00 R14: 0000000000000001 R15: 0000000000000000 account_kmem_nmi_safe mm/memcontrol.c:2760 [inline] obj_cgroup_charge_pages mm/memcontrol.c:2804 [inline] __memcg_kmem_charge_page+0xf7/0x240 mm/memcontrol.c:2844 __alloc_frozen_pages_noprof+0x1b5/0x370 mm/page_alloc.c:5165 __alloc_pages_noprof mm/page_alloc.c:5182 [inline] alloc_pages_bulk_noprof+0x560/0x710 mm/page_alloc.c:5102 alloc_pages_bulk_mempolicy_noprof+0x341/0x1650 mm/mempolicy.c:2724 vm_area_alloc_pages mm/vmalloc.c:3616 [inline] __vmalloc_area_node mm/vmalloc.c:3720 [inline] __vmalloc_node_range_noprof+0x733/0x12f0 mm/vmalloc.c:3893 __vmalloc_node_noprof mm/vmalloc.c:3956 [inline] __vmalloc_noprof+0xb1/0xf0 mm/vmalloc.c:3970 bpf_prog_alloc_no_stats+0x4a/0x4d0 kernel/bpf/core.c:106 bpf_prog_alloc+0x3c/0x1a0 kernel/bpf/core.c:153 bpf_prog_load+0x735/0x19e0 kernel/bpf/syscall.c:2966 __sys_bpf+0x507/0x860 kernel/bpf/syscall.c:6134 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline] __se_sys_bpf kernel/bpf/syscall.c:6242 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6242 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: 0033:0x7fc63418eec9 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:00007fc63504a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fc6343e5fa0 RCX: 00007fc63418eec9 RDX: 0000000000000094 RSI: 0000200000000580 RDI: 0000000000000005 RBP: 00007fc634211f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc6343e6038 R14: 00007fc6343e5fa0 R15: 00007ffe6e094f28 Allocated by task 10066: 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+0x7a3/0xab0 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+0x219/0x270 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 5934: 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 ffff88804f46ccc0 which belongs to the cache xfrm_state of size 928 The buggy address is located 48 bytes inside of freed 928-byte region [ffff88804f46ccc0, ffff88804f46d060) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804f46c440 pfn:0x4f46c 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 ffff8881462bd3c0 dead000000000122 0000000000000000 raw: ffff88804f46c440 00000000800f000e 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff8881462bd3c0 dead000000000122 0000000000000000 head: ffff88804f46c440 00000000800f000e 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00013d1b01 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 8843, tgid 8841 (syz.3.715), ts 206097931350, free_ts 205960516670 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_add_acquire+0xf7/0xb20 net/xfrm/xfrm_user.c:2990 xfrm_user_rcv_msg+0x7a3/0xab0 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+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 page last free pid 8808 tgid 8808 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_large_kmalloc+0x13a/0x1f0 mm/slub.c:4820 device_release+0x99/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 netdev_run_todo+0xd2e/0xea0 net/core/dev.c:11513 tun_detach drivers/net/tun.c:640 [inline] tun_chr_close+0x13c/0x1c0 drivers/net/tun.c:3433 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88804f46cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804f46cc00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc >ffff88804f46cc80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff88804f46cd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804f46cd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 4 bytes skipped: 0: df 80 3c 08 00 74 filds 0x7400083c(%rax) 6: 08 4c 89 ef or %cl,-0x11(%rcx,%rcx,4) a: e8 7c 7e f8 ff call 0xfff87e8b f: 4c 63 f5 movslq %ebp,%r14 12: 4d 8b 6d 00 mov 0x0(%r13),%r13 16: 41 80 fc 29 cmp $0x29,%r12b 1a: 0f 83 7c 01 00 00 jae 0x19c 20: 65 4f 01 74 e5 18 add %r14,%gs:0x18(%r13,%r12,8) * 26: 83 fb 36 cmp $0x36,%ebx <-- trapping instruction 29: 48 8b 3c 24 mov (%rsp),%rdi 2d: 0f 87 e4 00 00 00 ja 0x117 33: 89 d8 mov %ebx,%eax 35: 48 rex.W 36: b9 60 00 00 00 mov $0x60,%ecx