================================================================== BUG: KASAN: use-after-free in hlist_move_list include/linux/list.h:852 [inline] BUG: KASAN: use-after-free in __collect_expired_timers kernel/time/timer.c:1484 [inline] BUG: KASAN: use-after-free in collect_expired_timers kernel/time/timer.c:1719 [inline] BUG: KASAN: use-after-free in __run_timers+0x4a8/0x6b0 kernel/time/timer.c:1783 Write of size 8 at addr ffff8881c21871c8 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.210-syzkaller-00019-g035e4939365c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18e/0x1d5 lib/dump_stack.c:118 print_address_description+0x8c/0x630 mm/kasan/report.c:384 __kasan_report+0xf6/0x130 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 hlist_move_list include/linux/list.h:852 [inline] __collect_expired_timers kernel/time/timer.c:1484 [inline] collect_expired_timers kernel/time/timer.c:1719 [inline] __run_timers+0x4a8/0x6b0 kernel/time/timer.c:1783 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1800 __do_softirq+0x23e/0x643 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x195/0x1c0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:538 [inline] smp_apic_timer_interrupt+0x113/0x440 arch/x86/kernel/apic/apic.c:1150 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:831 RIP: 0010:default_idle+0x1f/0x30 arch/x86/kernel/process.c:573 Code: 90 90 90 90 90 90 90 90 90 90 90 e8 1b 2b fd fd bf 01 00 00 00 89 c6 e8 ef 26 07 fd 0f 1f 44 00 00 0f 00 2d 93 67 65 00 fb f4 fc 2a fd fd bf ff ff ff ff 89 c6 e9 d0 26 07 fd 41 57 41 56 53 RSP: 0018:ffffffff85a07e88 EFLAGS: 000002d6 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffffffff85a18a00 RCX: ffffffff85a18a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffffffff821d1134 R09: fffffbfff0b43141 R10: fffffbfff0b43141 R11: 1ffffffff0b43140 R12: 0000000000000000 R13: 1ffffffff0b43140 R14: ffffffff86069520 R15: 0000000000000000 default_idle_call kernel/sched/idle.c:94 [inline] cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1d2/0x590 kernel/sched/idle.c:264 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:356 start_kernel+0x6c2/0x76d init/main.c:1046 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 The buggy address belongs to the page: page:ffffea00070861c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x8000000000000000() raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 2, migratetype Unmovable, gfp_mask 0x146dc0(GFP_USER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__GFP_ZERO) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x194/0x380 mm/page_alloc.c:2171 get_page_from_freelist+0x524/0x560 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x2ab/0x6f0 mm/page_alloc.c:4857 __alloc_pages include/linux/gfp.h:503 [inline] __alloc_pages_node include/linux/gfp.h:516 [inline] alloc_pages_node include/linux/gfp.h:530 [inline] kmalloc_order mm/slab_common.c:1342 [inline] kmalloc_order_trace+0x2a/0xf0 mm/slab_common.c:1358 __kmalloc_node include/linux/slab.h:422 [inline] kmalloc_node include/linux/slab.h:599 [inline] kvmalloc_node+0x7e/0xf0 mm/util.c:596 kvmalloc include/linux/mm.h:759 [inline] kvzalloc include/linux/mm.h:767 [inline] alloc_netdev_mqs+0x86/0xc30 net/core/dev.c:9597 tun_set_iff+0x4f9/0x1050 drivers/net/tun.c:2825 __tun_chr_ioctl+0x6c7/0x1b70 drivers/net/tun.c:3160 do_vfs_ioctl+0x6d1/0x15b0 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:742 [inline] __do_sys_ioctl fs/ioctl.c:749 [inline] __se_sys_ioctl fs/ioctl.c:747 [inline] __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] __free_pages_ok+0x7ee/0x920 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4919 [inline] __free_pages+0x45/0x1e0 mm/page_alloc.c:4925 kfree+0x1ef/0x260 mm/slub.c:4068 device_release+0x70/0x1a0 drivers/base/core.c:1776 kobject_cleanup lib/kobject.c:708 [inline] kobject_release+0x20c/0x330 lib/kobject.c:739 tun_set_iff+0xc0b/0x1050 drivers/net/tun.c:2917 __tun_chr_ioctl+0x6c7/0x1b70 drivers/net/tun.c:3160 do_vfs_ioctl+0x6d1/0x15b0 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:742 [inline] __do_sys_ioctl fs/ioctl.c:749 [inline] __se_sys_ioctl fs/ioctl.c:747 [inline] __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Memory state around the buggy address: ffff8881c2187080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881c2187100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881c2187180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881c2187200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881c2187280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: e8 1b 2b fd fd callq 0xfdfd2b2b 10: bf 01 00 00 00 mov $0x1,%edi 15: 89 c6 mov %eax,%esi 17: e8 ef 26 07 fd callq 0xfd07270b 1c: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 21: 0f 00 2d 93 67 65 00 verw 0x656793(%rip) # 0x6567bb 28: fb sti 29: f4 hlt * 2a: e8 fc 2a fd fd callq 0xfdfd2b2b <-- trapping instruction 2f: bf ff ff ff ff mov $0xffffffff,%edi 34: 89 c6 mov %eax,%esi 36: e9 d0 26 07 fd jmpq 0xfd07270b 3b: 41 57 push %r15 3d: 41 56 push %r14 3f: 53 push %rbx