8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 00000018 when write
[00000018] *pgd=8c1d3003, *pmd=fe7ff003
Internal error: Oops: a07 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 13571 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at pagemap_scan_init_bounce_buffer fs/proc/task_mmu.c:2399 [inline]
PC is at do_pagemap_scan+0x294/0x6b4 fs/proc/task_mmu.c:2445
LR is at kmalloc_array include/linux/slab.h:665 [inline]
LR is at pagemap_scan_init_bounce_buffer fs/proc/task_mmu.c:2394 [inline]
LR is at do_pagemap_scan+0x260/0x6b4 fs/proc/task_mmu.c:2445
pc : [<8059d3ac>]    lr : [<8059d378>]    psr: 20000013
sp : eca2de18  ip : 00000000  fp : eca2df04
r10: eca2de50  r9 : 8c012400  r8 : 00000000
r7 : 00000000  r6 : 00000000  r5 : 20ffa000  r4 : 84298000
r3 : 20ffb000  r2 : 00000000  r1 : 00000000  r0 : 00000010
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 30c5387d  Table: 8c082d40  DAC: fffffffd
Register r0 information: zero-size pointer
Register r1 information: NULL pointer
Register r2 information: NULL pointer
Register r3 information: non-paged memory
Register r4 information: slab mm_struct start 84298000 pointer offset 0 size 712
Register r5 information: non-paged memory
Register r6 information: NULL pointer
Register r7 information: NULL pointer
Register r8 information: NULL pointer
Register r9 information: slab task_struct start 8c012400 pointer offset 0 size 3072
Register r10 information: 2-page vmalloc region starting at 0xeca2c000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796
Register r11 information: 2-page vmalloc region starting at 0xeca2c000 allocated at kernel_clone+0xac/0x3cc kernel/fork.c:2796
Register r12 information: NULL pointer
Process syz-executor.0 (pid: 13571, stack limit = 0xeca2c000)
Stack: (0xeca2de18 to 0xeca2e000)
de00:                                                       00000000 00000000
de20: 10000000 20000cc0 00000001 00000000 00000000 20ffa000 00000000 00000000
de40: 00000000 00000000 00000000 00000000 00000060 00000000 00000000 00000000
de60: 20ffa000 00000000 20ffb000 00000000 00000000 00000000 20000c80 00000000
de80: 00000000 10000000 ffffffff 00000000 00000000 00000000 00000000 00000000
dea0: 00000000 00000000 00000000 00000000 00000000 00000000 00000010 00000000
dec0: 00000000 00000000 20000c80 00000000 c0606610 d5cbc77d eca2def4 c0606610
dee0: 00000000 847ec241 20000cc0 00000003 8c012400 847ec240 eca2df14 eca2df08
df00: 8059d7f4 8059d124 eca2dfa4 eca2df18 8050f8cc 8059d7d8 8c012400 00000001
df20: ecac8b10 8c012400 eca2df44 eca2df38 81896d50 81896c1c eca2df5c eca2df48
df40: 8024c840 8027b054 40000000 eca2dfb0 eca2df84 eca2df60 8020316c 8024c7fc
df60: 8261ca0c eca2dfb0 0006b3f0 ecac8b10 80203054 d5cbc77d eca2dfac 00000000
df80: 00000000 0014c2c8 00000036 80200288 8c012400 00000036 00000000 eca2dfa8
dfa0: 80200060 8050f7c0 00000000 00000000 00000003 c0606610 20000cc0 00000000
dfc0: 00000000 00000000 0014c2c8 00000036 7ed6232e 7ed6232f 003d0f00 76b1c0fc
dfe0: 76b1bf08 76b1bef8 000167f8 00050bc0 60000010 00000003 00000000 00000000
Backtrace: 
[<8059d118>] (do_pagemap_scan) from [<8059d7f4>] (do_pagemap_cmd+0x28/0x34 fs/proc/task_mmu.c:2512)
 r10:847ec240 r9:8c012400 r8:00000003 r7:20000cc0 r6:847ec241 r5:00000000
 r4:c0606610
[<8059d7cc>] (do_pagemap_cmd) from [<8050f8cc>] (vfs_ioctl fs/ioctl.c:51 [inline])
[<8059d7cc>] (do_pagemap_cmd) from [<8050f8cc>] (do_vfs_ioctl fs/ioctl.c:858 [inline])
[<8059d7cc>] (do_pagemap_cmd) from [<8050f8cc>] (__do_sys_ioctl fs/ioctl.c:902 [inline])
[<8059d7cc>] (do_pagemap_cmd) from [<8050f8cc>] (sys_ioctl+0x118/0xc24 fs/ioctl.c:890)
[<8050f7b4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66)
Exception stack(0xeca2dfa8 to 0xeca2dff0)
dfa0:                   00000000 00000000 00000003 c0606610 20000cc0 00000000
dfc0: 00000000 00000000 0014c2c8 00000036 7ed6232e 7ed6232f 003d0f00 76b1c0fc
dfe0: 76b1bf08 76b1bef8 000167f8 00050bc0
 r10:00000036 r9:8c012400 r8:80200288 r7:00000036 r6:0014c2c8 r5:00000000
 r4:00000000
Code: e51b309c e51b208c e50b203c e3a02000 (e1c060f8) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e51b309c 	ldr	r3, [fp, #-156]	@ 0xffffff64
   4:	e51b208c 	ldr	r2, [fp, #-140]	@ 0xffffff74
   8:	e50b203c 	str	r2, [fp, #-60]	@ 0xffffffc4
   c:	e3a02000 	mov	r2, #0
* 10:	e1c060f8 	strd	r6, [r0, #8] <-- trapping instruction