BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 1d4565067 P4D 1d4565067 PUD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 830 Comm: syz.0.126 Not tainted 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:ffff8881f6f09cf0 EFLAGS: 00010202 RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881f21fde80 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881e2b831c0 RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003 R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffff9a10 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e2b831c0 FS: 00007fd1841a96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d8760000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 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:__sanitizer_cov_trace_const_cmp8+0x1f/0x80 kernel/kcov.c:283 Code: 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 48 8b 45 08 65 48 8b 15 c0 0a a3 7e 65 8b 0d c5 0a a3 7e f7 c1 00 01 1f 00 74 02 <5d> c3 8b 8a 00 0a 00 00 83 f9 03 75 f3 48 8b 8a 08 0a 00 00 44 8b RSP: 0018:ffff8881f0dcf610 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81849f84 RBX: dead000000000100 RCX: 0000000000000000 RDX: ffff8881f21fde80 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8881f0dcf610 R08: dffffc0000000000 R09: fffff94000edabc1 R10: fffff94000edabc1 R11: 1ffffd4000edabc0 R12: dffffc0000000000 R13: ffffea00076d5e00 R14: 1ffffd4000edabc1 R15: ffff8881e2169560 page_mapcount include/linux/mm.h:824 [inline] zap_pte_range mm/memory.c:1106 [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+0xef4/0x1b20 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_group_exit+0x13e/0x300 kernel/exit.c:984 get_signal+0xdee/0x13d0 kernel/signal.c:2738 do_signal+0xad/0xda0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0xc4/0x1b0 arch/x86/entry/common.c:159 prepare_exit_to_usermode+0x18e/0x1f0 arch/x86/entry/common.c:194 syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x13e/0x170 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7fd185b40969 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:00007fd1841a9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffff4 RBX: 00007fd185d67fa0 RCX: 00007fd185b40969 RDX: 0000200000000080 RSI: 00000000400454ca RDI: 0000000000000006 RBP: 00007fd185bc2ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd185d67fa0 R15: 00007ffda7e96608 Modules linked in: CR2: 0000000000000000 ---[ end trace 84f82ba11e8708a5 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09cf0 EFLAGS: 00010202 RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881f21fde80 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881e2b831c0 RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003 R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffff9a10 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e2b831c0 FS: 00007fd1841a96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001d8760000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 7: 00 00 00 00 b: 55 push %rbp c: 48 89 e5 mov %rsp,%rbp f: 48 8b 45 08 mov 0x8(%rbp),%rax 13: 65 48 8b 15 c0 0a a3 mov %gs:0x7ea30ac0(%rip),%rdx # 0x7ea30adb 1a: 7e 1b: 65 8b 0d c5 0a a3 7e mov %gs:0x7ea30ac5(%rip),%ecx # 0x7ea30ae7 22: f7 c1 00 01 1f 00 test $0x1f0100,%ecx 28: 74 02 je 0x2c * 2a: 5d pop %rbp <-- trapping instruction 2b: c3 ret 2c: 8b 8a 00 0a 00 00 mov 0xa00(%rdx),%ecx 32: 83 f9 03 cmp $0x3,%ecx 35: 75 f3 jne 0x2a 37: 48 8b 8a 08 0a 00 00 mov 0xa08(%rdx),%rcx 3e: 44 rex.R 3f: 8b .byte 0x8b