================================================================== BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:791 [inline] BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:824 [inline] BUG: KASAN: use-after-free in expire_timers kernel/time/timer.c:1482 [inline] BUG: KASAN: use-after-free in __run_timers+0x7be/0xbe0 kernel/time/timer.c:1817 Write of size 8 at addr ffff8881cfb571c8 by task syz.1.15/447 CPU: 1 PID: 447 Comm: syz.1.15 Not tainted 5.4.290-syzkaller-00017-g6b07fcd94a6a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 __hlist_del include/linux/list.h:791 [inline] detach_timer kernel/time/timer.c:824 [inline] expire_timers kernel/time/timer.c:1482 [inline] __run_timers+0x7be/0xbe0 kernel/time/timer.c:1817 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830 __do_softirq+0x23b/0x6b7 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:539 [inline] smp_apic_timer_interrupt+0x11a/0x490 arch/x86/kernel/apic/apic.c:1161 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:free_unref_page_list+0x539/0x590 mm/page_alloc.c:3178 Code: ff 0d c7 9a 72 7e 48 8b 74 24 30 0f 85 68 fe ff ff e8 6b 61 70 ff e9 5e fe ff ff 48 8b 44 24 18 48 89 44 24 50 ff 74 24 50 9d <48> c7 44 24 60 0e 36 e0 45 48 b8 00 00 00 00 00 fc ff df 48 8b 4c RSP: 0018:ffff8881e9b57160 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000246 RBX: 1ffffd4000e7495d RCX: dffffc0000000000 RDX: ffffea00073a5308 RSI: ffff8881f6f5c320 RDI: ffffea00073a4ac8 RBP: ffff8881e9b57270 R08: ffffffff8231cdb9 R09: ffffed1039d25600 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea00073a4ae8 R13: ffff8881e9b57320 R14: ffff8881e9b57320 R15: 000000000000000f release_pages+0xad8/0xb20 mm/swap.c:842 __pagevec_release+0xc3/0x150 mm/swap.c:862 pagevec_release include/linux/pagevec.h:88 [inline] shmem_undo_range+0x8a5/0x1ad0 mm/shmem.c:875 shmem_truncate_range mm/shmem.c:997 [inline] shmem_evict_inode+0x218/0x9a0 mm/shmem.c:1097 evict+0x4ea/0x960 fs/inode.c:610 __dentry_kill+0x429/0x630 fs/dcache.c:583 dentry_kill+0xb8/0x280 fs/dcache.c:677 dput+0x3c/0x80 fs/dcache.c:864 __fput+0x443/0x680 fs/file_table.c:294 task_work_run+0x140/0x170 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xcaf/0x2bc0 kernel/exit.c:861 do_group_exit+0x138/0x300 kernel/exit.c:984 get_signal+0xdb1/0x1440 kernel/signal.c:2738 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159 prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194 ret_from_intr+0x1c/0x1c RIP: 0033:0x7f79e5e35171 Code: Bad RIP value. RSP: 002b:00004000000001a0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f79e604dfa0 RCX: 00007f79e5e35169 RDX: 00004000000002c0 RSI: 00004000000001a0 RDI: 0000000000020000 RBP: 00007f79e5eb62a0 R08: 0000400000000380 R09: 0000400000000380 R10: 0000400000000300 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f79e604dfa0 R15: 00007ffdd214b138 Allocated by task 411: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 shmem_alloc_inode+0x16/0x30 mm/shmem.c:3719 alloc_inode fs/inode.c:231 [inline] new_inode_pseudo+0x60/0x210 fs/inode.c:966 new_inode+0x25/0x1d0 fs/inode.c:995 shmem_get_inode+0x10b/0x620 mm/shmem.c:2252 shmem_symlink+0x118/0x5f0 mm/shmem.c:3068 vfs_symlink+0x36c/0x500 fs/namei.c:4276 do_symlinkat+0x19b/0x400 fs/namei.c:4303 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 17: 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+0x1b5/0x270 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch+0x492/0xa00 kernel/rcu/tree.c:2167 rcu_core+0x4c8/0xcb0 kernel/rcu/tree.c:2387 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292 The buggy address belongs to the object at ffff8881cfb57090 which belongs to the cache shmem_inode_cache of size 760 The buggy address is located 312 bytes inside of 760-byte region [ffff8881cfb57090, ffff8881cfb57388) The buggy address belongs to the page: page:ffffea00073ed500 refcount:1 mapcount:0 mapping:ffff8881f5cffb80 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5cffb80 raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, 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+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0x109/0x250 mm/slub.c:2842 shmem_alloc_inode+0x16/0x30 mm/shmem.c:3719 alloc_inode fs/inode.c:231 [inline] new_inode_pseudo+0x60/0x210 fs/inode.c:966 new_inode+0x25/0x1d0 fs/inode.c:995 shmem_get_inode+0x10b/0x620 mm/shmem.c:2252 shmem_mknod+0x54/0x1a0 mm/shmem.c:2844 lookup_open fs/namei.c:3379 [inline] do_last fs/namei.c:3471 [inline] path_openat+0x184a/0x34b0 fs/namei.c:3683 do_filp_open+0x20b/0x450 fs/namei.c:3713 do_sys_open+0x39c/0x810 fs/open.c:1123 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+0x847/0x950 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4955 [inline] __free_pages mm/page_alloc.c:4961 [inline] free_pages+0xf6/0x1b0 mm/page_alloc.c:4969 stack_depot_save+0x42b/0x480 lib/stackdepot.c:300 save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x21c/0x270 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kfree+0x123/0x370 mm/slub.c:4071 kobject_cleanup lib/kobject.c:722 [inline] kobject_release lib/kobject.c:747 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21a/0x2f0 lib/kobject.c:764 netdev_queue_update_kobjects+0x337/0x3a0 net/core/net-sysfs.c:1610 remove_queue_kobjects net/core/net-sysfs.c:1663 [inline] netdev_unregister_kobject+0x10c/0x240 net/core/net-sysfs.c:1816 rollback_registered_many+0xed6/0x1330 net/core/dev.c:8674 unregister_netdevice_many net/core/dev.c:9805 [inline] default_device_exit_batch+0x3e0/0x680 net/core/dev.c:10276 ops_exit_list net/core/net_namespace.c:187 [inline] cleanup_net+0x6e2/0xc90 net/core/net_namespace.c:612 process_one_work+0x765/0xd20 kernel/workqueue.c:2290 worker_thread+0xaef/0x1470 kernel/workqueue.c:2436 kthread+0x2da/0x360 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354 Memory state around the buggy address: ffff8881cfb57080: fc fc fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cfb57100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881cfb57180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881cfb57200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cfb57280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 1ec740067 P4D 1ec740067 PUD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 447 Comm: syz.1.15 Tainted: G B 5.4.290-syzkaller-00017-g6b07fcd94a6a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010006 RAX: ffffffff8154e8ca RBX: 0000000000000100 RCX: ffff8881ee23ee40 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881cfb571c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff9820 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881cfb571c0 FS: 00007f79e449f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001eb12e000 CR4: 00000000003406a0 DR0: 0000400000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: call_timer_fn+0x36/0x390 kernel/time/timer.c:1448 expire_timers kernel/time/timer.c:1488 [inline] __run_timers+0x8a5/0xbe0 kernel/time/timer.c:1817 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830 __do_softirq+0x23b/0x6b7 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:539 [inline] smp_apic_timer_interrupt+0x11a/0x490 arch/x86/kernel/apic/apic.c:1161 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:free_unref_page_list+0x539/0x590 mm/page_alloc.c:3178 Code: ff 0d c7 9a 72 7e 48 8b 74 24 30 0f 85 68 fe ff ff e8 6b 61 70 ff e9 5e fe ff ff 48 8b 44 24 18 48 89 44 24 50 ff 74 24 50 9d <48> c7 44 24 60 0e 36 e0 45 48 b8 00 00 00 00 00 fc ff df 48 8b 4c RSP: 0018:ffff8881e9b57160 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000246 RBX: 1ffffd4000e7495d RCX: dffffc0000000000 RDX: ffffea00073a5308 RSI: ffff8881f6f5c320 RDI: ffffea00073a4ac8 RBP: ffff8881e9b57270 R08: ffffffff8231cdb9 R09: ffffed1039d25600 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea00073a4ae8 R13: ffff8881e9b57320 R14: ffff8881e9b57320 R15: 000000000000000f release_pages+0xad8/0xb20 mm/swap.c:842 __pagevec_release+0xc3/0x150 mm/swap.c:862 pagevec_release include/linux/pagevec.h:88 [inline] shmem_undo_range+0x8a5/0x1ad0 mm/shmem.c:875 shmem_truncate_range mm/shmem.c:997 [inline] shmem_evict_inode+0x218/0x9a0 mm/shmem.c:1097 evict+0x4ea/0x960 fs/inode.c:610 __dentry_kill+0x429/0x630 fs/dcache.c:583 dentry_kill+0xb8/0x280 fs/dcache.c:677 dput+0x3c/0x80 fs/dcache.c:864 __fput+0x443/0x680 fs/file_table.c:294 task_work_run+0x140/0x170 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xcaf/0x2bc0 kernel/exit.c:861 do_group_exit+0x138/0x300 kernel/exit.c:984 get_signal+0xdb1/0x1440 kernel/signal.c:2738 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159 prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194 ret_from_intr+0x1c/0x1c RIP: 0033:0x7f79e5e35171 Code: Bad RIP value. RSP: 002b:00004000000001a0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f79e604dfa0 RCX: 00007f79e5e35169 RDX: 00004000000002c0 RSI: 00004000000001a0 RDI: 0000000000020000 RBP: 00007f79e5eb62a0 R08: 0000400000000380 R09: 0000400000000380 R10: 0000400000000300 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f79e604dfa0 R15: 00007ffdd214b138 Modules linked in: CR2: 0000000000000000 ---[ end trace 19b1909820f23463 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010006 RAX: ffffffff8154e8ca RBX: 0000000000000100 RCX: ffff8881ee23ee40 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881cfb571c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff9820 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881cfb571c0 FS: 00007f79e449f6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001eb12e000 CR4: 00000000003406a0 DR0: 0000400000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 ---------------- Code disassembly (best guess): 0: ff 0d c7 9a 72 7e decl 0x7e729ac7(%rip) # 0x7e729acd 6: 48 8b 74 24 30 mov 0x30(%rsp),%rsi b: 0f 85 68 fe ff ff jne 0xfffffe79 11: e8 6b 61 70 ff call 0xff706181 16: e9 5e fe ff ff jmp 0xfffffe79 1b: 48 8b 44 24 18 mov 0x18(%rsp),%rax 20: 48 89 44 24 50 mov %rax,0x50(%rsp) 25: ff 74 24 50 push 0x50(%rsp) 29: 9d popf * 2a: 48 c7 44 24 60 0e 36 movq $0x45e0360e,0x60(%rsp) <-- trapping instruction 31: e0 45 33: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 3a: fc ff df 3d: 48 rex.W 3e: 8b .byte 0x8b 3f: 4c rex.WR