syzbot
BUG: unable to handle kernel paging request in jbd2_journal_file_inode
Status:
upstream: reported C repro on 2026/11/12 15:16
Reported-by: syzbot+d222c5648db184c949a9@syzkaller.appspotmail.com
First crash: 22h29m, last: 8h01m
Sample crash report:
EXT4-fs: Ignoring removed i_version option
EXT4-fs (loop0): Using encoding defined by superblock: utf8-12.1.0 with flags 0x0
EXT4-fs (loop0): mounted filesystem with ordered data mode. Quota mode: journalled.
Unable to handle kernel paging request at virtual address dfff800000000005
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
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
[dfff800000000005] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4530 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : jbd2_journal_file_inode+0xe0/0x41c fs/jbd2/transaction.c:2698
lr : spin_lock include/linux/spinlock.h:351 [inline]
lr : jbd2_journal_file_inode+0xd8/0x41c fs/jbd2/transaction.c:2697
sp : ffff8000220775d0
x29: ffff8000220775d0 x28: ffff0000e0b08d68 x27: 0000000000000800
x26: 1fffe00019ee24c0 x25: dfff800000000000 x24: ffff0000d565c000
x23: 0000000000000006 x22: 0000000000000000 x21: 00000000000007ff
x20: ffff0000cf712600 x19: 0000000000000000 x18: 1fffe00033c2597e
x17: 0000000000000000 x16: ffff8000082f5420 x15: 000000000004ffff
x14: ffff70000440eea0 x13: 1ffff0000440eea0 x12: 0000000000000004
x11: ffffffffffffffff x10: dfff800000000000 x9 : edda72c3ce465900
x8 : 0000000000000005 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff8000197096b8 x4 : 0000000000000008 x3 : ffff8000082f5548
x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
jbd2_journal_file_inode+0xe0/0x41c fs/jbd2/transaction.c:2698
jbd2_journal_inode_ranged_write+0x44/0x58 fs/jbd2/transaction.c:2742
ext4_jbd2_inode_add_write fs/ext4/ext4_jbd2.h:424 [inline]
ext4_map_blocks+0xe4c/0x160c fs/ext4/inode.c:769
ext4_convert_inline_data_nolock+0x360/0xa80 fs/ext4/inline.c:1265
ext4_convert_inline_data+0x39c/0x4fc fs/ext4/inline.c:2136
ext4_setattr+0xb64/0x15e4 fs/ext4/inode.c:5605
notify_change+0xb5c/0xe20 fs/attr.c:499
do_truncate+0x188/0x20c fs/open.c:65
vfs_truncate+0x23c/0x2b0 fs/open.c:111
do_sys_truncate+0xec/0x1b4 fs/open.c:134
__do_sys_truncate fs/open.c:146 [inline]
__se_sys_truncate fs/open.c:144 [inline]
__arm64_sys_truncate+0x5c/0x70 fs/open.c:144
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x12c 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:589
Code: 911da300 95c455d3 9100a268 d343fd08 (38796908)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
0: 911da300 add x0, x24, #0x768
4: 95c455d3 bl 0x7115750
8: 9100a268 add x8, x19, #0x28
c: d343fd08 lsr x8, x8, #3
* 10: 38796908 ldrb w8, [x8, x25] <-- trapping instruction
* Struck through repros no longer work on HEAD.