syzbot

Unable to handle kernel paging request at virtual address dfff800000000006
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
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
[dfff800000000006] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4443 Comm: syz-executor 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 : write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline]
pc : lmLogSync+0x230/0x8b0 fs/jfs/jfs_logmgr.c:937
lr : write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
lr : lmLogSync+0x20c/0x8b0 fs/jfs/jfs_logmgr.c:937
sp : ffff8000209977c0
x29: ffff800020997890 x28: 1ffff00002a41a68 x27: dfff800000000000
x26: 0000000000000002 x25: 1fffe0001a94442c x24: ffff8000209977e0
x23: dfff800000000000 x22: ffff700004132efc x21: 0000000000000030
x20: ffff0000cbacb638 x19: ffff0000d4f73800 x18: ffff800011b8bf60
x17: 1fffe00033eac97e x16: ffff8000082d0ff8 x15: 0000000000000000
x14: 0000000000000009 x13: 1ffff00004132edc x12: 0000000000ff0100
x11: ff008000086dd438 x10: 0000000000000000 x9 : 9c12c38fe95b1200
x8 : 0000000000000006 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000008 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline]
 lmLogSync+0x230/0x8b0 fs/jfs/jfs_logmgr.c:937
 jfs_syncpt+0x70/0x94 fs/jfs/jfs_logmgr.c:1041
 jfs_sync_fs+0x8c/0xac fs/jfs/super.c:685
 sync_filesystem+0x1a0/0x218 fs/sync.c:66
 generic_shutdown_super+0x70/0x324 fs/super.c:474
 kill_block_super+0x70/0xdc fs/super.c:1470
 deactivate_locked_super+0xac/0x120 fs/super.c:332
 deactivate_super+0xe4/0x104 fs/super.c:363
 cleanup_mnt+0x390/0x418 fs/namespace.c:1191
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1198
 task_work_run+0x1ec/0x278 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 do_notify_resume+0x1fa0/0x2aa4 arch/arm64/kernel/signal.c:1151
 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_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638
 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: 97c09e7f f94002a8 9100c115 d343fea8 (387b6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97c09e7f 	bl	0xffffffffff0279fc
   4:	f94002a8 	ldr	x8, [x21]
   8:	9100c115 	add	x21, x8, #0x30
   c:	d343fea8 	lsr	x8, x21, #3
* 10:	387b6908 	ldrb	w8, [x8, x27] <-- trapping instruction