syzbot

EXT4-fs error (device loop0): ext4_dirty_inode:6133: inode #3: comm syz.0.17: mark_inode_dirty error
EXT4-fs error (device loop0): ext4_do_update_inode:5268: inode #3: comm syz.0.17: corrupted inode contents
EXT4-fs error (device loop0): __ext4_ext_dirty:206: inode #3: comm syz.0.17: mark_inode_dirty error
Unable to handle kernel paging request at virtual address ffffffffffffff93
KASAN: maybe wild-memory-access in range [0x0003fffffffffc98-0x0003fffffffffc9f]
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
swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000020dfcc000
[ffffffffffffff93] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4497 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ext4_ext_drop_refs fs/ext4/extents.c:119 [inline]
pc : ext4_free_ext_path fs/ext4/extents.c:128 [inline]
pc : ext4_ext_map_blocks+0x2a70/0x570c fs/ext4/extents.c:4497
lr : ext4_ext_map_blocks+0x1528/0x570c fs/ext4/extents.c:4438
sp : ffff800021406800
x29: ffff800021406a80 x28: dfff800000000000 x27: 0000000000000001
x26: ffff800021406cc0 x25: 0000000000000001 x24: 0000000000000001
x23: 0000000000000001 x22: 0000000000000042 x21: 0000000000000029
x20: ffff800021406cc0 x19: ffffffffffffff8b x18: ffff800011b9bf60
x17: ffff80001835a000 x16: ffff8000082d7db8 x15: ffff800017e3b000
x14: 0000000000000001 x13: 1fffe000180c3f11 x12: 0000000000ff0100
x11: ff00800008db745c x10: 0000000000000000 x9 : 7de237244664a300
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000080 x4 : ffff0000c061f1d0 x3 : ffff800008a90998
x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffffffffffffff93
Call trace:
 ext4_ext_drop_refs fs/ext4/extents.c:119 [inline]
 ext4_free_ext_path fs/ext4/extents.c:128 [inline]
 ext4_ext_map_blocks+0x2a70/0x570c fs/ext4/extents.c:4497
 ext4_map_blocks+0x860/0x1778 fs/ext4/inode.c:679
 ext4_getblk+0x178/0x664 fs/ext4/inode.c:890
 ext4_bread+0x3c/0x1a8 fs/ext4/inode.c:946
 ext4_quota_write+0x204/0x534 fs/ext4/super.c:7222
 write_blk fs/quota/quota_tree.c:70 [inline]
 get_free_dqblk+0x284/0x574 fs/quota/quota_tree.c:136
 do_insert_tree+0x1c4/0xc34 fs/quota/quota_tree.c:347
 do_insert_tree+0x790/0xc34 fs/quota/quota_tree.c:402
 do_insert_tree+0x790/0xc34 fs/quota/quota_tree.c:402
 do_insert_tree+0x790/0xc34 fs/quota/quota_tree.c:402
 dq_insert_tree fs/quota/quota_tree.c:432 [inline]
 qtree_write_dquot+0x3d4/0x4f0 fs/quota/quota_tree.c:451
 v2_write_dquot+0xf0/0x180 fs/quota/quota_v2.c:361
 dquot_acquire+0x2a8/0x4d8 fs/quota/dquot.c:472
 ext4_acquire_dquot+0x270/0x428 fs/ext4/super.c:6831
 dqget+0x654/0xcc4 fs/quota/dquot.c:988
 __dquot_initialize+0x2fc/0xacc fs/quota/dquot.c:1517
 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1579
 ext4_process_orphan+0x5c/0x2b4 fs/ext4/orphan.c:327
 ext4_orphan_cleanup+0x920/0x1060 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5556 [inline]
 ext4_fill_super+0x6188/0x660c fs/ext4/super.c:5687
 get_tree_bdev+0x358/0x544 fs/super.c:1366
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5717
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x228/0x810 fs/namespace.c:3078
 path_mount+0x5bc/0xe80 fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount fs/namespace.c:3606 [inline]
 __arm64_sys_mount+0x49c/0x59c fs/namespace.c:3606
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 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: 2a1803fb d343fc08 38fc6908 35006ba8 (79401276) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	2a1803fb 	mov	w27, w24
   4:	d343fc08 	lsr	x8, x0, #3
   8:	38fc6908 	ldrsb	w8, [x8, x28]
   c:	35006ba8 	cbnz	w8, 0xd80
* 10:	79401276 	ldrh	w22, [x19, #8] <-- trapping instruction