BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 0 P4D 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 2236 Comm: syz.4.529 Tainted: G W 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09cf0 EFLAGS: 00010202 RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881ea3b8fc0 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881df5971c0 RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003 R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffa3d8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881df5971c0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d6cad000 CR4: 00000000003406b0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: call_timer_fn+0x3c/0x380 kernel/time/timer.c:1448 expire_timers kernel/time/timer.c:1493 [inline] __run_timers+0x81d/0xb60 kernel/time/timer.c:1817 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1830 __do_softirq+0x236/0x660 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x197/0x1c0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:539 [inline] smp_apic_timer_interrupt+0x11d/0x490 arch/x86/kernel/apic/apic.c:1161 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:153 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x50 kernel/kcov.c:187 Code: 00 00 00 48 c7 c7 00 96 d1 85 e8 6b f2 2d 00 5d c3 00 00 90 90 00 00 90 90 00 55 48 89 e5 48 8b 45 08 65 48 8b 0d 90 0e a3 7e <65> 8b 15 95 0e a3 7e f7 c2 00 01 1f 00 74 02 5d c3 8b 91 00 0a 00 RSP: 0018:ffff8881c000f990 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81849dca RBX: ffffea00076e41c8 RCX: ffff8881ea3b8fc0 RDX: ffff8881ea3b8fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8881c000f990 R08: dffffc0000000000 R09: ffffed103d4771f9 R10: ffffed103d4771f9 R11: 1ffff1103d4771f8 R12: dffffc0000000000 R13: ffffea00076e41c0 R14: 1ffffd4000edc839 R15: dead000000000100 compound_head include/linux/page-flags.h:176 [inline] PageAnon include/linux/page-flags.h:463 [inline] zap_pte_range mm/memory.c:1095 [inline] zap_pmd_range mm/memory.c:1222 [inline] zap_pud_range mm/memory.c:1251 [inline] zap_p4d_range mm/memory.c:1272 [inline] unmap_page_range+0xd3a/0x1b20 mm/memory.c:1293 unmap_single_vma mm/memory.c:1338 [inline] unmap_vmas+0x245/0x340 mm/memory.c:1370 exit_mmap+0x2bb/0x520 mm/mmap.c:3191 __mmput+0x92/0x2e0 kernel/fork.c:1101 mmput+0x47/0x60 kernel/fork.c:1122 exit_mm kernel/exit.c:538 [inline] do_exit+0x99f/0x2660 kernel/exit.c:848 __do_sys_exit kernel/exit.c:953 [inline] __se_sys_exit kernel/exit.c:951 [inline] __x64_sys_exit+0x40/0x40 kernel/exit.c:951 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f6e87860969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6e85ec8fe8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 00007f6e87a87fa0 RCX: 00007f6e87860969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f6e878e2ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6e87a87fa0 R15: 00007ffefdeebe28 Modules linked in: CR2: 0000000000000000 ---[ end trace 8925221ab195a2a6 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09cf0 EFLAGS: 00010202 RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881ea3b8fc0 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881df5971c0 RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003 R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffa3d8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881df5971c0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d6cad000 CR4: 00000000003406b0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 48 c7 add %cl,-0x39(%rax) 5: c7 00 96 d1 85 e8 movl $0xe885d196,(%rax) b: 6b f2 2d imul $0x2d,%edx,%esi e: 00 5d c3 add %bl,-0x3d(%rbp) 11: 00 00 add %al,(%rax) 13: 90 nop 14: 90 nop 15: 00 00 add %al,(%rax) 17: 90 nop 18: 90 nop 19: 00 55 48 add %dl,0x48(%rbp) 1c: 89 e5 mov %esp,%ebp 1e: 48 8b 45 08 mov 0x8(%rbp),%rax 22: 65 48 8b 0d 90 0e a3 mov %gs:0x7ea30e90(%rip),%rcx # 0x7ea30eba 29: 7e * 2a: 65 8b 15 95 0e a3 7e mov %gs:0x7ea30e95(%rip),%edx # 0x7ea30ec6 <-- trapping instruction 31: f7 c2 00 01 1f 00 test $0x1f0100,%edx 37: 74 02 je 0x3b 39: 5d pop %rbp 3a: c3 ret 3b: 8b .byte 0x8b 3c: 91 xchg %eax,%ecx 3d: 00 0a add %cl,(%rdx)