EXT4-fs error (device loop2) in ext4_reserve_inode_write:5929: Corrupt filesystem
EXT4-fs error (device loop2): __ext4_ext_dirty:206: inode #18: comm syz.2.651: 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: 7964 Comm: syz.2.651 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 : ffff800021926460
x29: ffff8000219266e0 x28: dfff800000000000 x27: 0000000000000001
x26: ffff800021926920 x25: 0000000000000001 x24: 0000000000000001
x23: 0000000000000001 x22: 0000000000000002 x21: 0000000000000071
x20: ffff800021926920 x19: ffffffffffffff8b x18: ffff800011b9bf60
x17: 1fffe00033ea637e x16: ffff8000082d7db8 x15: ffff80001521d000
x14: 0000000000000001 x13: 1fffe0001c0040ba x12: 0000000000ff0100
x11: ff00800008db745c x10: 0000000000000000 x9 : aec92022899dd700
x8 : 0000000000000000 x7 : ffff800008257984 x6 : 0000000000000000
x5 : 0000000000000080 x4 : ffff0000e0020658 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_get_block+0x19c/0x4d8 fs/ext4/inode.c:822
 ext4_get_block+0x4c/0x60 fs/ext4/inode.c:839
 ext4_block_write_begin+0x50c/0x10e4 fs/ext4/inode.c:1124
 ext4_write_begin+0x5f4/0x131c fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x348/0x990 fs/ext4/inode.c:3000
 generic_perform_write+0x234/0x4f4 mm/filemap.c:3862
 ext4_buffered_write_iter+0x2c4/0x528 fs/ext4/file.c:285
 ext4_file_write_iter+0x18c/0x1574 fs/ext4/file.c:-1
 __kernel_write_iter+0x208/0x56c fs/read_write.c:517
 __kernel_write+0xe8/0x148 fs/read_write.c:537
 __dump_emit fs/coredump.c:873 [inline]
 dump_emit+0x224/0x324 fs/coredump.c:910
 elf_core_dump+0x2120/0x2da0 fs/binfmt_elf.c:2306
 do_coredump+0x10cc/0x1c68 fs/coredump.c:824
 get_signal+0xdec/0x1304 kernel/signal.c:2857
 do_signal arch/arm64/kernel/signal.c:1095 [inline]
 do_notify_resume+0x28c/0x2aa4 arch/arm64/kernel/signal.c:1148
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_da+0xb4/0x144 arch/arm64/kernel/entry-common.c:516
 el0t_64_sync_handler+0x90/0xf0 arch/arm64/kernel/entry-common.c:658
 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