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BUG: unable to handle kernel paging request in udf_fiiter_write_fi

Status: upstream: reported C repro on 2025/06/09 11:18
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+f1cc2b579bf84a64d8c8@syzkaller.appspotmail.com
First crash: 30d, last: 26d
Bug presence (2)
Date Name Commit Repro Result
2025/06/14 linux-6.1.y (ToT) 58485ff1a74f C [report] BUG: unable to handle kernel paging request in udf_fiiter_write_fi
2025/06/14 upstream (ToT) 4774cfe3543a C Didn't crash
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 BUG: unable to handle kernel paging request in udf_fiiter_write_fi origin:lts-only 8 C 1 11d 14d 0/3 upstream: reported C repro on 2025/06/26 07:14
upstream general protection fault in udf_fiiter_write_fi udf 2 C error 2 909d 913d 22/29 fixed on 2023/06/08 14:41
linux-6.1 general protection fault in udf_fiiter_write_fi 2 1 242d 242d 0/3 auto-obsoleted due to no activity on 2025/02/18 06:56

Sample crash report:
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: 0 PID: 4297 Comm: syz-executor921 Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : udf_fiiter_write_fi+0x178/0xaa8 fs/udf/directory.c:405
lr : udf_fiiter_write_fi+0xd8/0xaa8 fs/udf/directory.c:401
sp : ffff8000207d74d0
x29: ffff8000207d7540 x28: ffff0000e01b1d60 x27: ffff8000207d76f0
x26: dfff800000000000 x25: 1ffff000040faf12 x24: 0000000000000200
x23: 0000000000000000 x22: ffff0000d76e87c0 x21: 0000000000000001
x20: 0000000000000028 x19: ffff8000207d7890 x18: 0000000000000000
x17: 000000000000001c x16: ffff8000082d1c00 x15: 0000000000000000
x14: 000000003b9aca00 x13: 000000001c03a180 x12: 0000000000ff0100
x11: ff008000098292dc x10: 0000000000000000 x9 : ffff0000d52c9bc0
x8 : 0000000000000005 x7 : 000000001c03a180 x6 : 0000000000000028
x5 : ffff0000d76e81e0 x4 : ffff0000d76e81d0 x3 : ffff800009814e68
x2 : 0000000000000010 x1 : 0000000000000000 x0 : 0000000000000003
Call trace:
 udf_fiiter_write_fi+0x178/0xaa8 fs/udf/directory.c:405
 udf_rename+0x960/0xa10 fs/udf/namei.c:860
 vfs_rename+0x954/0xdcc fs/namei.c:4874
 do_renameat2+0x738/0xa54 fs/namei.c:5027
 __do_sys_renameat2 fs/namei.c:5060 [inline]
 __se_sys_renameat2 fs/namei.c:5057 [inline]
 __arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5057
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 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: 97c2b1f6 f9400288 9100a114 d343fe88 (387a6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	97c2b1f6 	bl	0xffffffffff0ac7d8
   4:	f9400288 	ldr	x8, [x20]
   8:	9100a114 	add	x20, x8, #0x28
   c:	d343fe88 	lsr	x8, x20, #3
* 10:	387a6908 	ldrb	w8, [x8, x26] <-- trapping instruction

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/09 11:17 linux-6.1.y 58485ff1a74f 4826c28e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 BUG: unable to handle kernel paging request in udf_fiiter_write_fi
* Struck through repros no longer work on HEAD.