[syzbot] [btrfs?] BUG: unable to handle kernel paging request in find_first_extent_item

[syzbot <syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    573067a5a685 Merge branch 'for-next/core' into for-kernelci
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=1256d0b0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cd7202b56d469648
dashboard link: https://syzkaller.appspot.com/bug?extid=339e9dbe3a2ca419b85d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1254c818580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=172486df980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9d3b5c855aa0/disk-573067a5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0c06fc1ead83/vmlinux-573067a5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3390e59b9e4b/Image-573067a5.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/0d8dc2ed77bb/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com

BTRFS info (device loop0): scrub: started on devid 1
Unable to handle kernel paging request at virtual address dfff800000000041
KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[dfff800000000041] address between user and kernel address ranges
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 UID: 0 PID: 6417 Comm: syz-executor153 Not tainted 6.13.0-rc3-syzkaller-g573067a5a685 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : find_first_extent_item+0xac/0x674 fs/btrfs/scrub.c:1375
lr : find_first_extent_item+0xa4/0x674 fs/btrfs/scrub.c:1374
sp : ffff8000a5be6e60
x29: ffff8000a5be6f80 x28: dfff800000000000 x27: 0000000000000000
x26: 0000000000400000 x25: 0000000000400000 x24: 1fffe0001848ab0a
x23: 0000000000000208 x22: ffff8000a5be6f20 x21: ffff0000c2455858
x20: ffff8000a5be6ec0 x19: ffff0000db072010 x18: ffff0000db072010
x17: 000000000000e32c x16: ffff80008b5fea08 x15: 0000000000000004
x14: 1fffe0001b60c031 x13: 0000000000000000 x12: ffff700014b7cdd8
x11: ffff80008257f234 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000041 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000008 x3 : 0000000000400000
x2 : 0000000000100000 x1 : ffff0000db072010 x0 : 0000000000000000
Call trace:
 find_first_extent_item+0xac/0x674 fs/btrfs/scrub.c:1375 (P)
 scrub_find_fill_first_stripe+0x2c0/0xab8 fs/btrfs/scrub.c:1551
 queue_scrub_stripe fs/btrfs/scrub.c:1921 [inline]
 scrub_simple_mirror+0x440/0x7e4 fs/btrfs/scrub.c:2152
 scrub_stripe+0x7e4/0x2174 fs/btrfs/scrub.c:2317
 scrub_chunk+0x268/0x41c fs/btrfs/scrub.c:2443
 scrub_enumerate_chunks+0xd38/0x1784 fs/btrfs/scrub.c:2707
 btrfs_scrub_dev+0x5a8/0xb34 fs/btrfs/scrub.c:3029
 btrfs_ioctl_scrub+0x1f4/0x3e8 fs/btrfs/ioctl.c:3248
 btrfs_ioctl+0x6a8/0xb04 fs/btrfs/ioctl.c:5246
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: b900118a 97847832 91082377 d343fee8 (387c6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	b900118a 	str	w10, [x12, #16]
   4:	97847832 	bl	0xfffffffffe11e0cc
   8:	91082377 	add	x23, x27, #0x208
   c:	d343fee8 	lsr	x8, x23, #3
* 10:	387c6908 	ldrb	w8, [x8, x28] <-- trapping instruction


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