syzbot

loop0: detected capacity change from 0 to 64
Unable to handle kernel paging request at virtual address dfff800000000008
KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047]
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
[dfff800000000008] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4227 Comm: syz-executor207 Not tainted 6.1.87-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
pstate: 80401005 (Nzcv daif +PAN -UAO -TCO -DIT +SSBS BTYPE=--)
pc : hfs_find_init+0x6c/0x1c8 fs/hfs/bfind.c:21
lr : hfs_find_init+0x30/0x1c8 fs/hfs/bfind.c:16
sp : ffff80001dde6ff0
x29: ffff80001dde6ff0 x28: ffff700003bbce14 x27: 0000000000000004
x26: ffff0000de360180 x25: 0000000000000008 x24: dfff800000000000
x23: ffff0000de36014c x22: ffff80001dde70d8 x21: 0000000000000040
x20: ffff80001dde70c0 x19: 0000000000000000 x18: ffff80001dde6b60
x17: ffff8000188dd000 x16: ffff8000120aafc0 x15: ffff8000183c2f80
x14: 0000000016002719 x13: dfff800000000000 x12: 0000000000000007
x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff80000909b230
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff800018a0a818 x4 : 0000000000000000 x3 : 0000000000000030
x2 : 0000000000000008 x1 : ffff80001dde70c0 x0 : ffff80001dde70d0
Call trace:
 hfs_find_init+0x6c/0x1c8 fs/hfs/bfind.c:21
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_get_block+0x29c/0x9e0 fs/hfs/extent.c:366
 block_read_full_folio+0x2f4/0x98c fs/buffer.c:2271
 hfs_read_folio+0x28/0x38 fs/hfs/inode.c:39
 filemap_read_folio+0x14c/0x39c mm/filemap.c:2461
 do_read_cache_folio+0x24c/0x544 mm/filemap.c:3598
 do_read_cache_page mm/filemap.c:3640 [inline]
 read_cache_page+0x6c/0x180 mm/filemap.c:3649
 read_mapping_page include/linux/pagemap.h:791 [inline]
 hfs_btree_open+0x440/0x1010 fs/hfs/btree.c:78
 hfs_mdb_get+0x10cc/0x1c2c fs/hfs/mdb.c:199
 hfs_fill_super+0xd64/0x13b4 fs/hfs/super.c:406
 mount_bdev+0x274/0x370 fs/super.c:1432
 hfs_mount+0x44/0x58 fs/hfs/super.c:456
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
 vfs_get_tree+0x90/0x274 fs/super.c:1562
 do_new_mount+0x278/0x8fc fs/namespace.c:3051
 path_mount+0x590/0xe5c fs/namespace.c:3381
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount fs/namespace.c:3579 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3579
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 97e36ff7 91010275 f90002df d343feb9 (38f86b28) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97e36ff7 	bl	0xffffffffff8dbfdc
   4:	91010275 	add	x21, x19, #0x40
   8:	f90002df 	str	xzr, [x22]
   c:	d343feb9 	lsr	x25, x21, #3
* 10:	38f86b28 	ldrsb	w8, [x25, x24] <-- trapping instruction