8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 00000018 when write
[00000018] *pgd=84b08003, *pmd=84b39003, *pte=00000000
Internal error: Oops: a07 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 1 PID: 3837 Comm: syz-executor.1 Not tainted 6.7.0-rc7-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at pagemap_scan_init_bounce_buffer fs/proc/task_mmu.c:2383 [inline]
PC is at do_pagemap_scan+0x308/0x698 fs/proc/task_mmu.c:2430
LR is at 0x10
pc : [<80581334>]    lr : [<00000010>]    psr: 20000013
sp : dfc35dd0  ip : 00000000  fp : dfc35eb4
r10: dfc35e00  r9 : 00000000  r8 : 83f0e000
r7 : 00000000  r6 : 82f38300  r5 : 20ffb000  r4 : 00000000
r3 : 20ffb000  r2 : 00000000  r1 : 00000000  r0 : 00000000
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 30c5387d  Table: 85f6dfc0  DAC: 00000000
Register r0 information: NULL pointer
Register r1 information: NULL pointer
Register r2 information: NULL pointer
Register r3 information: non-paged memory
Register r4 information: NULL pointer
Register r5 information: non-paged memory
Register r6 information: slab mm_struct start 82f38300 pointer offset 0 size 712
Register r7 information: NULL pointer
Register r8 information: slab task_struct start 83f0e000 pointer offset 0 size 3072
Register r9 information: NULL pointer
Register r10 information: 2-page vmalloc region starting at 0xdfc34000 allocated at kernel_clone+0xac/0x41c kernel/fork.c:2907
Register r11 information: 2-page vmalloc region starting at 0xdfc34000 allocated at kernel_clone+0xac/0x41c kernel/fork.c:2907
Register r12 information: NULL pointer
Process syz-executor.1 (pid: 3837, stack limit = 0xdfc34000)
Stack: (0xdfc35dd0 to 0xdfc36000)
5dc0:                                     00000000 00000000 06000000 20000080
5de0: 20ffb000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5e00: 00000060 00000000 00000000 00000000 20ffb000 00000000 20ffb000 00000000
5e20: 00000000 00000000 20000040 00000000 00000000 06000000 ffffffff 00000000
5e40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5e60: 00000000 00000000 00000010 00000000 00000000 00000000 20000040 00000000
5e80: c0606610 3bdfdece dfc35ea4 c0606610 00000000 8435cd81 20000080 8435cd80
5ea0: 00000003 83f0e000 dfc35ec4 dfc35eb8 805816ec 80581038 dfc35fa4 dfc35ec8
5ec0: 804f96a8 805816d0 00050af0 00000000 00000000 00000000 dfc35f04 dfc35ee8
5ee0: 8020c0ac 8020d078 00000000 00000001 8185e128 ecac8b10 dfc35f44 dfc35f08
5f00: 8020d100 8020c094 00000000 00000000 8020c954 dfc35fac 83f0e000 00000001
5f20: ecac8b10 83f0e000 dfc35f44 dfc35f38 81852ae8 818529b8 dfc35f5c dfc35f48
5f40: 8024c5d8 802792c8 40000000 dfc35fb0 dfc35f84 dfc35f60 802030e4 8024c594
5f60: 8261c928 dfc35fb0 0006b320 ecac8b10 80202fcc 3bdfdece dfc35fac 00000000
5f80: 00000000 0014c2c0 00000036 80200288 83f0e000 00000036 00000000 dfc35fa8
5fa0: 80200060 804f959c 00000000 00000000 00000003 c0606610 20000080 00000000
5fc0: 00000000 00000000 0014c2c0 00000036 7eea532e 7eea532f 003d0f00 76b0f0fc
5fe0: 76b0ef08 76b0eef8 000167a0 00050af0 60000010 00000003 00000000 00000000
Backtrace: 
[<8058102c>] (do_pagemap_scan) from [<805816ec>] (do_pagemap_cmd+0x28/0x34 fs/proc/task_mmu.c:2494)
 r10:83f0e000 r9:00000003 r8:8435cd80 r7:20000080 r6:8435cd81 r5:00000000
 r4:c0606610
[<805816c4>] (do_pagemap_cmd) from [<804f96a8>] (vfs_ioctl fs/ioctl.c:51 [inline])
[<805816c4>] (do_pagemap_cmd) from [<804f96a8>] (do_vfs_ioctl fs/ioctl.c:831 [inline])
[<805816c4>] (do_pagemap_cmd) from [<804f96a8>] (__do_sys_ioctl fs/ioctl.c:869 [inline])
[<805816c4>] (do_pagemap_cmd) from [<804f96a8>] (sys_ioctl+0x118/0xb58 fs/ioctl.c:857)
[<804f9590>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:66)
Exception stack(0xdfc35fa8 to 0xdfc35ff0)
5fa0:                   00000000 00000000 00000003 c0606610 20000080 00000000
5fc0: 00000000 00000000 0014c2c0 00000036 7eea532e 7eea532f 003d0f00 76b0f0fc
5fe0: 76b0ef08 76b0eef8 000167a0 00050af0
 r10:00000036 r9:83f0e000 r8:80200288 r7:00000036 r6:0014c2c0 r5:00000000
 r4:00000000
Code: e51b2098 e51b108c e50b103c e3a01000 (e1ce00f8) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	e51b2098 	ldr	r2, [fp, #-152]	@ 0xffffff68
   4:	e51b108c 	ldr	r1, [fp, #-140]	@ 0xffffff74
   8:	e50b103c 	str	r1, [fp, #-60]	@ 0xffffffc4
   c:	e3a01000 	mov	r1, #0
* 10:	e1ce00f8 	strd	r0, [lr, #8] <-- trapping instruction