8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 00000018 when write
[00000018] *pgd=853bd003, *pmd=fecd4003
Internal error: Oops: a07 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 10906 Comm: syz-executor.0 Not tainted 6.8.0-rc4-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at pagemap_scan_init_bounce_buffer fs/proc/task_mmu.c:2400 [inline]
PC is at do_pagemap_scan+0x29c/0x6c0 fs/proc/task_mmu.c:2446
LR is at kmalloc_array include/linux/slab.h:627 [inline]
LR is at pagemap_scan_init_bounce_buffer fs/proc/task_mmu.c:2395 [inline]
LR is at do_pagemap_scan+0x268/0x6c0 fs/proc/task_mmu.c:2446
pc : [<8058c580>]    lr : [<8058c54c>]    psr: 20000013
sp : eb939dc8  ip : 00000000  fp : eb939eb4
r10: eb939e00  r9 : 85209800  r8 : 00000000
r7 : 00000000  r6 : 00000000  r5 : 20ffb000  r4 : 85323c00
r3 : 20fff000  r2 : 00000000  r1 : 00000000  r0 : 00000010
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 8393b600  DAC: 00000000
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 85323c00 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 85209800 pointer offset 0 size 3072
Register r10 information: 2-page vmalloc region starting at 0xeb938000 allocated at kernel_clone+0xac/0x3c8 kernel/fork.c:2902
Register r11 information: 2-page vmalloc region starting at 0xeb938000 allocated at kernel_clone+0xac/0x3c8 kernel/fork.c:2902
Register r12 information: NULL pointer
Process syz-executor.0 (pid: 10906, stack limit = 0xeb938000)
Stack: (0xeb939dc8 to 0xeb93a000)
9dc0:                   00000000 00000000 10000000 200001c0 00000001 00000000
9de0: 00000000 20ffb000 00000000 00000000 00000000 00000000 00000000 00000000
9e00: 00000060 00000000 00000000 00000000 20ffb000 00000000 20fff000 00000000
9e20: 00000000 00000000 200000c0 00000000 00000000 10000000 ffffffff 00000000
9e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9e60: 00000000 00000000 00000010 00000000 00000000 00000000 200000c0 00000000
9e80: c0606610 b92de989 eb939ea4 c0606610 00000000 854f63c1 200001c0 854f63c0
9ea0: 00000003 85209800 eb939ec4 eb939eb8 8058c9cc 8058c2f0 eb939fa4 eb939ec8
9ec0: 80501d88 8058c9b0 00050bb0 00000000 00000000 00000000 eb939f04 eb939ee8
9ee0: 8020c124 8020d0f0 00000000 00000001 81860528 ecac8b10 eb939f44 eb939f08
9f00: 8020d178 8020c10c 000f4240 00000000 8020c9cc eb939fac 85209800 00000001
9f20: ecac8b10 85209800 eb939f44 eb939f38 81854e40 81854d10 eb939f5c eb939f48
9f40: 8024c7e8 802798f0 40000000 eb939fb0 eb939f84 eb939f60 80203134 8024c7a4
9f60: 8261c978 eb939fb0 0006b3e0 ecac8b10 8020301c b92de989 eb939fac 00000000
9f80: 00000000 0014c2c8 00000036 80200288 85209800 00000036 00000000 eb939fa8
9fa0: 80200060 80501c7c 00000000 00000000 00000003 c0606610 200001c0 00000000
9fc0: 00000000 00000000 0014c2c8 00000036 7ee4a32e 7ee4a32f 003d0f00 76bce0fc
9fe0: 76bcdf08 76bcdef8 000167e8 00050bb0 60000010 00000003 00000000 00000000
Backtrace: 
[<8058c2e4>] (do_pagemap_scan) from [<8058c9cc>] (do_pagemap_cmd+0x28/0x34 fs/proc/task_mmu.c:2513)
 r10:85209800 r9:00000003 r8:854f63c0 r7:200001c0 r6:854f63c1 r5:00000000
 r4:c0606610
[<8058c9a4>] (do_pagemap_cmd) from [<80501d88>] (vfs_ioctl fs/ioctl.c:51 [inline])
[<8058c9a4>] (do_pagemap_cmd) from [<80501d88>] (do_vfs_ioctl fs/ioctl.c:831 [inline])
[<8058c9a4>] (do_pagemap_cmd) from [<80501d88>] (__do_sys_ioctl fs/ioctl.c:869 [inline])
[<8058c9a4>] (do_pagemap_cmd) from [<80501d88>] (sys_ioctl+0x118/0xb58 fs/ioctl.c:857)
[<80501c70>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66)
Exception stack(0xeb939fa8 to 0xeb939ff0)
9fa0:                   00000000 00000000 00000003 c0606610 200001c0 00000000
9fc0: 00000000 00000000 0014c2c8 00000036 7ee4a32e 7ee4a32f 003d0f00 76bce0fc
9fe0: 76bcdf08 76bcdef8 000167e8 00050bb0
 r10:00000036 r9:85209800 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