================================================================== BUG: KASAN: slab-out-of-bounds in hlist_move_list include/linux/list.h:852 [inline] BUG: KASAN: slab-out-of-bounds in __collect_expired_timers kernel/time/timer.c:1484 [inline] BUG: KASAN: slab-out-of-bounds in collect_expired_timers kernel/time/timer.c:1719 [inline] BUG: KASAN: slab-out-of-bounds in __run_timers+0x4a8/0x6b0 kernel/time/timer.c:1783 Write of size 8 at addr ffff8881e89b31c8 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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 9b 2c fd fd bf 01 00 00 00 89 c6 e8 6f 28 07 fd 0f 1f 44 00 00 0f 00 2d 13 69 65 00 fb f4 7c 2c fd fd bf ff ff ff ff 89 c6 e9 50 28 07 fd 41 57 41 56 53 RSP: 0018:ffff8881f5df7e88 EFLAGS: 000002d6 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffff8881f5dc0fc0 RCX: ffff8881f5dc0fc0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffffffff821d1134 R09: ffffed103ebb81f9 R10: ffffed103ebb81f9 R11: 1ffff1103ebb81f8 R12: 0000000000000000 R13: 1ffff1103ebb81f8 R14: ffffffff860694e0 R15: 0000000000000001 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_secondary+0x312/0x390 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Allocated by task 155: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x131/0x1e0 mm/kasan/common.c:529 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] kernfs_iop_get_link+0x63/0x560 fs/kernfs/symlink.c:135 vfs_readlink+0x135/0x3a0 fs/namei.c:4815 do_readlinkat+0x23e/0x330 fs/stat.c:410 __do_sys_readlink fs/stat.c:431 [inline] __se_sys_readlink fs/stat.c:428 [inline] __x64_sys_readlink+0x7b/0x90 fs/stat.c:428 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 155: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x178/0x240 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook+0x80/0x150 mm/slub.c:1494 slab_free mm/slub.c:3080 [inline] kfree+0xc6/0x260 mm/slub.c:4071 do_delayed_call include/linux/delayed_call.h:28 [inline] vfs_readlink+0x210/0x3a0 fs/namei.c:4820 do_readlinkat+0x23e/0x330 fs/stat.c:410 __do_sys_readlink fs/stat.c:431 [inline] __se_sys_readlink fs/stat.c:428 [inline] __x64_sys_readlink+0x7b/0x90 fs/stat.c:428 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881e89b2000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 456 bytes to the right of 4096-byte region [ffff8881e89b2000, ffff8881e89b3000) The buggy address belongs to the page: page:ffffea0007a26c00 refcount:1 mapcount:0 mapping:ffff8881f5c0c280 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c0c280 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL) 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_slab_page+0x39/0x3e0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x450 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x320/0x4a0 mm/slub.c:2667 __slab_alloc+0x5a/0x90 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc+0x197/0x2b0 mm/slub.c:3909 kmalloc include/linux/slab.h:561 [inline] kzalloc include/linux/slab.h:690 [inline] ops_init+0x86/0x350 net/core/net_namespace.c:127 setup_net+0x1bb/0x9e0 net/core/net_namespace.c:338 copy_net_ns+0x31a/0x510 net/core/net_namespace.c:479 create_new_namespaces+0x4e3/0x5f0 kernel/nsproxy.c:103 copy_namespaces+0x169/0x1b0 kernel/nsproxy.c:161 copy_process+0x12a4/0x31f0 kernel/fork.c:2044 _do_fork+0x142/0x7f0 kernel/fork.c:2391 __do_sys_clone kernel/fork.c:2549 [inline] __se_sys_clone kernel/fork.c:2530 [inline] __x64_sys_clone+0x213/0x260 kernel/fork.c:2530 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: ffff8881e89b3080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e89b3100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881e89b3180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881e89b3200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e89b3280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 1de1a7067 P4D 1de1a7067 PUD 1de1a6067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 0 Comm: swapper/1 Tainted: G B 5.4.210-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d30 EFLAGS: 00010202 RAX: ffffffff8151cbb9 RBX: 0000000000000101 RCX: ffff8881f5dc0fc0 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e89b31c0 RBP: ffff8881e89b31e0 R08: ffffffff8151c992 R09: fffffbfff0d7370d R10: fffffbfff0d7370d R11: 1ffffffff0d7370c R12: 00000000ffffa1e0 R13: 1ffff1103ede92f1 R14: 0000000000000000 R15: ffff8881e89b31c0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001de1a4000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: call_timer_fn+0x31/0x350 kernel/time/timer.c:1418 expire_timers+0x21e/0x400 kernel/time/timer.c:1463 __run_timers+0x5b0/0x6b0 kernel/time/timer.c:1787 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 9b 2c fd fd bf 01 00 00 00 89 c6 e8 6f 28 07 fd 0f 1f 44 00 00 0f 00 2d 13 69 65 00 fb f4 7c 2c fd fd bf ff ff ff ff 89 c6 e9 50 28 07 fd 41 57 41 56 53 RSP: 0018:ffff8881f5df7e88 EFLAGS: 000002d6 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffff8881f5dc0fc0 RCX: ffff8881f5dc0fc0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffffffff821d1134 R09: ffffed103ebb81f9 R10: ffffed103ebb81f9 R11: 1ffff1103ebb81f8 R12: 0000000000000000 R13: 1ffff1103ebb81f8 R14: ffffffff860694e0 R15: 0000000000000001 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_secondary+0x312/0x390 arch/x86/kernel/smpboot.c:264 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Modules linked in: CR2: 0000000000000000 ---[ end trace b81cecdfe0e855ce ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d30 EFLAGS: 00010202 RAX: ffffffff8151cbb9 RBX: 0000000000000101 RCX: ffff8881f5dc0fc0 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e89b31c0 RBP: ffff8881e89b31e0 R08: ffffffff8151c992 R09: fffffbfff0d7370d R10: fffffbfff0d7370d R11: 1ffffffff0d7370c R12: 00000000ffffa1e0 R13: 1ffff1103ede92f1 R14: 0000000000000000 R15: ffff8881e89b31c0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001de1a4000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- 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 9b 2c fd fd callq 0xfdfd2cab 10: bf 01 00 00 00 mov $0x1,%edi 15: 89 c6 mov %eax,%esi 17: e8 6f 28 07 fd callq 0xfd07288b 1c: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 21: 0f 00 2d 13 69 65 00 verw 0x656913(%rip) # 0x65693b 28: fb sti 29: f4 hlt * 2a: e8 7c 2c fd fd callq 0xfdfd2cab <-- trapping instruction 2f: bf ff ff ff ff mov $0xffffffff,%edi 34: 89 c6 mov %eax,%esi 36: e9 50 28 07 fd jmpq 0xfd07288b 3b: 41 57 push %r15 3d: 41 56 push %r14 3f: 53 push %rbx