BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1e6964067 P4D 1e6964067 PUD 1e6967067 PMD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5842 Comm: syz.3.2099 Not tainted 5.4.276-syzkaller-00020-g4275fce9fe94 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202
RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881e79a5e80
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881ef1a71c0
RBP: ffff8881f6e09ec8 R08: ffffffff8154d0ce R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffb9b8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ef1a71c0
FS:  00007f97848ef6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001cde12000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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/0x460 arch/x86/kernel/apic/apic.c:1149
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:268 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:174 [inline]
RIP: 0010:PageAnon include/linux/page-flags.h:463 [inline]
RIP: 0010:mm_counter include/linux/mm.h:1801 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1104 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1222 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1251 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1272 [inline]
RIP: 0010:unmap_page_range+0xf8f/0x2620 mm/memory.c:1293
Code: 6d 06 00 00 e8 c2 6f d9 ff 4c 89 ff e8 4a 32 f7 ff 48 b8 00 00 00 00 00 fc ff df 41 80 3c 06 00 74 08 4c 89 e7 e8 c1 54 09 00 <49> 8b 1c 24 89 de 83 e6 01 31 ff e8 f1 72 d9 ff f6 c3 01 0f 85 b9
RSP: 0018:ffff8881e195f5a0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8881e79a5e80
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffff8881e195f790 R08: ffffffff8181fdb4 R09: fffff94000f20f89
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0007907c48
R13: ffff8881dd69e048 R14: 1ffffd4000f20f89 R15: ffffea0007907c40
 unmap_single_vma mm/memory.c:1338 [inline]
 unmap_vmas+0x355/0x4b0 mm/memory.c:1370
 exit_mmap+0x2bc/0x520 mm/mmap.c:3191
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:536 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:846
 do_group_exit+0x138/0x300 kernel/exit.c:982
 get_signal+0xdb1/0x1440 kernel/signal.c:2735
 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
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f978566db99
Code: Bad RIP value.
RSP: 002b:00007f97848ef048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffff4 RBX: 00007f97857fbfa0 RCX: 00007f978566db99
RDX: 0000000020000080 RSI: 00000000400454ca RDI: 0000000000000008
RBP: 00007f97856ee77e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f97857fbfa0 R15: 00007ffc82d0db68
Modules linked in:
CR2: 0000000000000000
---[ end trace 3a9c3f81b6ba36b2 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202
RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881e79a5e80
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881ef1a71c0
RBP: ffff8881f6e09ec8 R08: ffffffff8154d0ce R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffb9b8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ef1a71c0
FS:  00007f97848ef6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001cde12000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	e8 c2 6f d9 ff       	call   0xffd96fc9
   7:	4c 89 ff             	mov    %r15,%rdi
   a:	e8 4a 32 f7 ff       	call   0xfff73259
   f:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  16:	fc ff df
  19:	41 80 3c 06 00       	cmpb   $0x0,(%r14,%rax,1)
  1e:	74 08                	je     0x28
  20:	4c 89 e7             	mov    %r12,%rdi
  23:	e8 c1 54 09 00       	call   0x954e9
* 28:	49 8b 1c 24          	mov    (%r12),%rbx <-- trapping instruction
  2c:	89 de                	mov    %ebx,%esi
  2e:	83 e6 01             	and    $0x1,%esi
  31:	31 ff                	xor    %edi,%edi
  33:	e8 f1 72 d9 ff       	call   0xffd97329
  38:	f6 c3 01             	test   $0x1,%bl
  3b:	0f                   	.byte 0xf
  3c:	85                   	.byte 0x85
  3d:	b9                   	.byte 0xb9