syzbot

lmLogOpen: exit(-22)
jfs_dirty_inode called on read-only volume
Is remount racy?
jfs_dirty_inode called on read-only volume
Is remount racy?
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: 0 PID: 4519 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline]
pc : txBeginAnon+0xac/0x154 fs/jfs/jfs_txnmgr.c:466
lr : spin_lock include/linux/spinlock.h:351 [inline]
lr : txBeginAnon+0x78/0x154 fs/jfs/jfs_txnmgr.c:459
sp : ffff800020f873e0
x29: ffff800020f873e0 x28: ffff80001c5ac188 x27: ffff80001c5ac000
x26: ffff80001c5ac000 x25: 0000000000000008 x24: 0000000000000150
x23: dfff800000000000 x22: 0000000000000001 x21: 0000000000000000
x20: 0000000000000040 x19: ffff8000157c04a0 x18: ffff800011b7bf60
x17: ffff800018338000 x16: ffff8000082eeb30 x15: ffff800017e19000
x14: ffff7000041f0e64 x13: 1ffff000041f0e64 x12: 0000000000000004
x11: ffffffffffffffff x10: dfff800000000000 x9 : 06de9bbb4c41d100
x8 : 06de9bbb4c41d100 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff8000184ecf90 x4 : 0000000000000008 x3 : ffff8000082eec58
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 spin_lock include/linux/spinlock.h:351 [inline]
 txBeginAnon+0xac/0x154 fs/jfs/jfs_txnmgr.c:-1
 extAlloc+0xdc/0xdb8 fs/jfs/jfs_extent.c:78
 jfs_get_block+0x2c4/0x8c0 fs/jfs/inode.c:254
 __block_write_begin_int+0x350/0x1388 fs/buffer.c:1991
 __block_write_begin fs/buffer.c:2041 [inline]
 block_write_begin+0x98/0x11c fs/buffer.c:2102
 jfs_write_begin+0x44/0x88 fs/jfs/inode.c:310
 generic_perform_write+0x234/0x4f4 mm/filemap.c:3862
 __generic_file_write_iter+0x130/0x250 mm/filemap.c:3960
 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:3989
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x3ec/0x7f0 fs/read_write.c:584
 ksys_write+0x12c/0x224 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __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: aa1803e0 97ffff73 aa1303e0 959cacea (38776b28) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	aa1803e0 	mov	x0, x24
   4:	97ffff73 	bl	0xfffffffffffffdd0
   8:	aa1303e0 	mov	x0, x19
   c:	959cacea 	bl	0x672b3b4
* 10:	38776b28 	ldrb	w8, [x25, x23] <-- trapping instruction