[syzbot] BUG: unable to handle kernel paging request in kernfs_put_active

[syzbot <syzbot+258ad6d2cb6685e145bc@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    a6b443748715 Merge branch 'for-next/core', remote-tracking..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=17025144880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=14bf9ec0df433b27
dashboard link: https://syzkaller.appspot.com/bug?extid=258ad6d2cb6685e145bc
compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=106b8164880000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1040a75d080000

Downloadable assets:
disk image: https://storage.googleapis.com/81b491dd5861/disk-a6b44374.raw.xz
vmlinux: https://storage.googleapis.com/69c979cdc99a/vmlinux-a6b44374.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+258ad6d2cb6685e145bc@syzkaller.appspotmail.com

Unable to handle kernel paging request at virtual address 004065676e6168fb
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004
  CM = 0, WnR = 0
[004065676e6168fb] address between user and kernel address ranges
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 2562 Comm: udevd Not tainted 6.0.0-rc4-syzkaller-17255-ga6b443748715 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kernfs_lockdep fs/kernfs/dir.c:43 [inline]
pc : kernfs_put_active+0x24/0x11c fs/kernfs/dir.c:449
lr : kernfs_put_active+0x20/0x11c fs/kernfs/dir.c:443
sp : ffff800015fcbc50
x29: ffff800015fcbc50 x28: ffff0000c4810000 x27: 0001000000000000
x26: 0000000000000152 x25: ffff0000c538f348 x24: ffff8000086fe770
x23: ffff0000c92e5620 x22: 0000000000000007 x21: ffff0000cbc31500
x20: ffff8000086fba20 x19: 2f4065676e616863 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80000db78658 x15: ffff0000c4810000
x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c4810000
x11: ff808000086f6a0c x10: 0000000000000000 x9 : ffff8000086f6a0c
x8 : ffff0000c4810000 x7 : ffff8000095d8f84 x6 : 0000000000000000
x5 : 0000000000000080 x4 : ffff0001fefd3740 x3 : 0000000000083500
x2 : ffff0000c8aa3000 x1 : 0000000000000000 x0 : 2f4065676e616863
Call trace:
 kernfs_put_active+0x24/0x11c fs/kernfs/dir.c:446
 kernfs_fop_write_iter+0x1fc/0x294 fs/kernfs/file.c:358
 call_write_iter include/linux/fs.h:2187 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x2dc/0x46c fs/read_write.c:578
 ksys_write+0xb4/0x160 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __arm64_sys_write+0x24/0x34 fs/read_write.c:640
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
 el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:624
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642
 el0t_64_sync+0x18c/0x190
Code: aa1e03f4 aa0003f3 97eea9d1 b40004f3 (79413275) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa1e03f4 	mov	x20, x30
   4:	aa0003f3 	mov	x19, x0
   8:	97eea9d1 	bl	0xffffffffffbaa74c
   c:	b40004f3 	cbz	x19, 0xa8
* 10:	79413275 	ldrh	w21, [x19, #152] <-- trapping instruction


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