================================================================== 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 ffff8881ea1bb1c8 by task kworker/0:63/2263 CPU: 0 PID: 2263 Comm: kworker/0:63 Tainted: G W 5.4.290-syzkaller-00002-g41adfeb3d639 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: rcu_gp process_srcu 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:rdtsc_ordered arch/x86/include/asm/msr.h:236 [inline] RIP: 0010:delay_tsc+0x6f/0xd0 arch/x86/lib/delay.c:61 Code: 00 e8 a5 e9 ef fc 65 8b 05 5a 85 ad 7b 85 c0 74 2f f3 90 bf 01 00 00 00 e8 0e e8 ef fc e8 09 c4 dc fd 41 39 c7 75 20 0f 01 f9 <66> 90 48 89 d5 48 c1 e5 20 48 09 c5 48 29 dd 49 39 ee 77 be eb 23 RSP: 0018:ffff8881e6157be8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 00000000f56b2a8f RBX: 0000003bf56b0fdc RCX: 0000000000000000 RDX: 000000000000003b RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00000000000019bd R08: ffffffff8231cd01 R09: ffffed103cc2af81 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000001204 R13: 1ffffffff0c989d9 R14: 0000000000002af9 R15: 0000000000000000 try_check_zero+0x2f2/0x360 kernel/rcu/srcutree.c:708 srcu_advance_state kernel/rcu/srcutree.c:1146 [inline] process_srcu+0x1ab/0xc40 kernel/rcu/srcutree.c:1241 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 The buggy address belongs to the page: page:ffffea0007a86ec0 refcount:3 mapcount:2 mapping:0000000000000000 index:0x0 flags: 0x8000000000000000() raw: 8000000000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 0000000300000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO) 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 __vmalloc_area_node mm/vmalloc.c:2431 [inline] __vmalloc_node_range+0x384/0x710 mm/vmalloc.c:2499 vmalloc_user+0x70/0x80 mm/vmalloc.c:2629 kcov_mmap+0x28/0x120 kernel/kcov.c:450 call_mmap include/linux/fs.h:1996 [inline] mmap_region+0x110d/0x16f0 mm/mmap.c:1812 do_mmap+0x822/0xd30 mm/mmap.c:1581 do_mmap_pgoff include/linux/mm.h:2480 [inline] vm_mmap_pgoff+0x1b5/0x260 mm/util.c:528 ksys_mmap_pgoff+0x168/0x1e0 mm/mmap.c:1631 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 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_pcp_prepare mm/page_alloc.c:1233 [inline] free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085 free_unref_page mm/page_alloc.c:3134 [inline] free_the_page mm/page_alloc.c:4953 [inline] __free_pages+0xaf/0x140 mm/page_alloc.c:4961 __vunmap+0x75b/0x890 mm/vmalloc.c:2260 kcov_put kernel/kcov.c:396 [inline] kcov_close+0x27/0x50 kernel/kcov.c:495 __fput+0x262/0x680 fs/file_table.c:281 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 __do_sys_exit_group kernel/exit.c:995 [inline] __se_sys_exit_group kernel/exit.c:993 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:993 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Memory state around the buggy address: ffff8881ea1bb080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881ea1bb100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881ea1bb180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff8881ea1bb200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881ea1bb280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 1eae30067 P4D 1eae30067 PUD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 2263 Comm: kworker/0:63 Tainted: G B W 5.4.290-syzkaller-00002-g41adfeb3d639 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: rcu_gp process_srcu RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202 RAX: ffffffff8154e8ca RBX: 0000000000000101 RCX: ffff8881e5f1de80 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881ea1bb1c0 RBP: ffff8881f6e09ec8 R08: ffffffff8154e50e R09: ffffed103edc92a1 R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000ffffb700 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ea1bb1c0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d6b06000 CR4: 00000000003406b0 DR0: 0000000000000000 DR1: 0000200000000300 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:1493 [inline] __run_timers+0x879/0xbe0 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:rdtsc_ordered arch/x86/include/asm/msr.h:236 [inline] RIP: 0010:delay_tsc+0x6f/0xd0 arch/x86/lib/delay.c:61 Code: 00 e8 a5 e9 ef fc 65 8b 05 5a 85 ad 7b 85 c0 74 2f f3 90 bf 01 00 00 00 e8 0e e8 ef fc e8 09 c4 dc fd 41 39 c7 75 20 0f 01 f9 <66> 90 48 89 d5 48 c1 e5 20 48 09 c5 48 29 dd 49 39 ee 77 be eb 23 RSP: 0018:ffff8881e6157be8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 00000000f56b2a8f RBX: 0000003bf56b0fdc RCX: 0000000000000000 RDX: 000000000000003b RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00000000000019bd R08: ffffffff8231cd01 R09: ffffed103cc2af81 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000001204 R13: 1ffffffff0c989d9 R14: 0000000000002af9 R15: 0000000000000000 try_check_zero+0x2f2/0x360 kernel/rcu/srcutree.c:708 srcu_advance_state kernel/rcu/srcutree.c:1146 [inline] process_srcu+0x1ab/0xc40 kernel/rcu/srcutree.c:1241 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 Modules linked in: CR2: 0000000000000000 ---[ end trace 66a33443c22f96ec ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202 RAX: ffffffff8154e8ca RBX: 0000000000000101 RCX: ffff8881e5f1de80 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881ea1bb1c0 RBP: ffff8881f6e09ec8 R08: ffffffff8154e50e R09: ffffed103edc92a1 R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000ffffb700 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ea1bb1c0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d6b06000 CR4: 00000000003406b0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 ---------------- Code disassembly (best guess): 0: 00 e8 add %ch,%al 2: a5 movsl %ds:(%rsi),%es:(%rdi) 3: e9 ef fc 65 8b jmp 0x8b65fcf7 8: 05 5a 85 ad 7b add $0x7bad855a,%eax d: 85 c0 test %eax,%eax f: 74 2f je 0x40 11: f3 90 pause 13: bf 01 00 00 00 mov $0x1,%edi 18: e8 0e e8 ef fc call 0xfcefe82b 1d: e8 09 c4 dc fd call 0xfddcc42b 22: 41 39 c7 cmp %eax,%r15d 25: 75 20 jne 0x47 27: 0f 01 f9 rdtscp * 2a: 66 90 xchg %ax,%ax <-- trapping instruction 2c: 48 89 d5 mov %rdx,%rbp 2f: 48 c1 e5 20 shl $0x20,%rbp 33: 48 09 c5 or %rax,%rbp 36: 48 29 dd sub %rbx,%rbp 39: 49 39 ee cmp %rbp,%r14 3c: 77 be ja 0xfffffffc 3e: eb 23 jmp 0x63