================================================================== 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+0x9e5/0xa30 net/xfrm/xfrm_state.c:830 Write of size 8 at addr ffff88806e718470 by task swapper/2/0 CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 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+0x9e5/0xa30 net/xfrm/xfrm_state.c:830 xfrm_timer_handler+0x86c/0xf10 net/xfrm/xfrm_state.c:716 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 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+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 2d 64 02 e9 13 0a 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 53 65 18 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc9000047fdf8 EFLAGS: 00000286 RAX: 00000000000f1369 RBX: 0000000000000002 RCX: ffffffff8b91ab29 RDX: 0000000000000000 RSI: ffffffff8de4f58a RDI: ffffffff8c163800 RBP: ffffed1003bdf910 R08: 0000000000000001 R09: ffffed1005686655 R10: ffff88802b4332ab R11: 0000000000000000 R12: 0000000000000002 R13: ffff88801defc880 R14: ffffffff90abac90 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 Allocated by task 6822: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 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+0x1cb/0x3b0 mm/slub.c:4247 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733 __find_acq_core+0xb59/0x2900 net/xfrm/xfrm_state.c:1833 xfrm_find_acq+0x7b/0xa0 net/xfrm/xfrm_state.c:2353 xfrm_alloc_userspi+0x58e/0xbb0 net/xfrm/xfrm_user.c:1863 xfrm_user_rcv_msg+0x4fb/0xb60 net/xfrm/xfrm_user.c:3501 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3523 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x300 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 10: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 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+0x2d1/0x4d0 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+0x50a/0x770 net/xfrm/xfrm_state.c:634 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x730 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 ffff88806e718440 which belongs to the cache xfrm_state of size 928 The buggy address is located 48 bytes inside of freed 928-byte region [ffff88806e718440, ffff88806e7187e0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806e719100 pfn:0x6e718 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff888040f09040 dead000000000122 0000000000000000 raw: ffff88806e719100 00000000801e0019 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff888040f09040 dead000000000122 0000000000000000 head: ffff88806e719100 00000000801e0019 00000000f5000000 0000000000000000 head: 04fff00000000003 ffffea0001b9c601 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6776, tgid 6775 (syz.3.309), ts 60230555359, free_ts 59841563079 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab mm/slub.c:2660 [inline] new_slab+0x247/0x330 mm/slub.c:2714 ___slab_alloc+0xcf2/0x1750 mm/slub.c:3901 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992 __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4247 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733 __find_acq_core+0xb59/0x2900 net/xfrm/xfrm_state.c:1833 xfrm_find_acq+0x7b/0xa0 net/xfrm/xfrm_state.c:2353 xfrm_alloc_userspi+0x58e/0xbb0 net/xfrm/xfrm_user.c:1863 xfrm_user_rcv_msg+0x4fb/0xb60 net/xfrm/xfrm_user.c:3501 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3523 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 page last free pid 5971 tgid 5971 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2758 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3223 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 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] __kmalloc_cache_noprof+0x1f1/0x3e0 mm/slub.c:4402 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kernfs_fop_open+0x244/0xda0 fs/kernfs/file.c:641 do_dentry_open+0x97f/0x1530 fs/open.c:965 vfs_open+0x82/0x3f0 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x1de4/0x2cb0 fs/namei.c:4046 do_filp_open+0x20b/0x470 fs/namei.c:4073 do_sys_openat2+0x11b/0x1d0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88806e718300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806e718380: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806e718400: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff88806e718480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806e718500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 64 02 e9 fs add %cl,%ch 3: 13 0a adc (%rdx),%ecx 5: 03 00 add (%rax),%eax 7: 0f 1f 00 nopl (%rax) a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: f3 0f 1e fa endbr64 1e: eb 07 jmp 0x27 20: 0f 00 2d 53 65 18 00 verw 0x186553(%rip) # 0x18657a 27: fb sti 28: f4 hlt * 29: c3 ret <-- trapping instruction 2a: cc int3 2b: cc int3 2c: cc int3 2d: cc int3 2e: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 35: 00 00 00 38: 66 90 xchg %ax,%ax 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop