BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1e44d8067 P4D 1e44d8067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 1499 Comm: syz.0.328 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:ffff8881f6e09cf0 EFLAGS: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881e68dbf00
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881ed6bb1c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffff9ec8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ed6bb1c0
FS:  00007fbeaaf6b6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001e380b000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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
 </IRQ>
RIP: 0010:PageAnon include/linux/page-flags.h:464 [inline]
RIP: 0010:page_remove_rmap+0x84/0x800 mm/rmap.c:1316
Code: c4 01 0f 85 ae 06 00 00 e8 89 7f d7 ff 49 89 dc 49 83 c4 18 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 9c 79 05 00 <4d> 8b 34 24 44 89 f6 83 e6 01 31 ff e8 2b 83 d7 ff 41 f6 c6 01 75
RSP: 0018:ffff8881e43975d8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffffd4000edb8e3 RBX: ffffea00076dc700 RCX: ffff8881e68dbf00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8881e4397610 R08: dffffc0000000000 R09: fffff94000edb8e1
R10: fffff94000edb8e1 R11: 1ffffd4000edb8e0 R12: ffffea00076dc718
R13: dffffc0000000000 R14: ffffea00076dc708 R15: 0000000000000000
 zap_pte_range mm/memory.c:1105 [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+0xe8f/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: 0033:0x7fbeac902969
Code: Bad RIP value.
RSP: 002b:00007fbeaaf6b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: 0000000000000000 RBX: 00007fbeacb29fa0 RCX: 00007fbeac902969
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007fbeac984ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000840 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbeacb29fa0 R15: 00007fff14a768b8
Modules linked in:
CR2: 0000000000000000
---[ end trace 81bc305f7dbf5d4a ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09cf0 EFLAGS: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881e68dbf00
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881ed6bb1c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffff9ec8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ed6bb1c0
FS:  00007fbeaaf6b6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001e380b000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	0f 85 ae 06 00 00    	jne    0x6b4
   6:	e8 89 7f d7 ff       	call   0xffd77f94
   b:	49 89 dc             	mov    %rbx,%r12
   e:	49 83 c4 18          	add    $0x18,%r12
  12:	4c 89 e0             	mov    %r12,%rax
  15:	48 c1 e8 03          	shr    $0x3,%rax
  19:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
  1e:	74 08                	je     0x28
  20:	4c 89 e7             	mov    %r12,%rdi
  23:	e8 9c 79 05 00       	call   0x579c4
* 28:	4d 8b 34 24          	mov    (%r12),%r14 <-- trapping instruction
  2c:	44 89 f6             	mov    %r14d,%esi
  2f:	83 e6 01             	and    $0x1,%esi
  32:	31 ff                	xor    %edi,%edi
  34:	e8 2b 83 d7 ff       	call   0xffd78364
  39:	41 f6 c6 01          	test   $0x1,%r14b
  3d:	75                   	.byte 0x75