linux-kernel - [syzbot] [udf?] WARNING in __getblk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Message-ID: <688b0ef3.a00a0220.26d0e1.0038.GAE@google.com>
Date: Wed, 30 Jul 2025 23:36:35 -0700
From: syzbot <syzbot+89fa933c2012e808890e@...kaller.appspotmail.com>
To: jack@...e.com, linux-kernel@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [udf?] WARNING in __getblk_slow

Hello,

syzbot found the following issue on:

HEAD commit:    ced1b9e0392d Merge tag 'ata-6.17-rc1' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=154e9782580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a6d3e67bfa86ec9a
dashboard link: https://syzkaller.appspot.com/bug?extid=89fa933c2012e808890e
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11da74a2580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12af8cf0580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7992028cc1d8/disk-ced1b9e0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/21e8b1538aee/vmlinux-ced1b9e0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/04d1cab11b26/bzImage-ced1b9e0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+89fa933c2012e808890e@...kaller.appspotmail.com

syz.1.17: attempt to access beyond end of device
nbd1: rw=0, sector=64, nr_sectors = 1 limit=0
------------[ cut here ]------------
WARNING: CPU: 1 PID: 6081 at fs/buffer.c:1125 __getblk_slow+0x4cc/0x560 fs/buffer.c:1125
Modules linked in:
CPU: 1 UID: 0 PID: 6081 Comm: syz.1.17 Not tainted 6.16.0-syzkaller-00857-gced1b9e0392d #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__getblk_slow+0x4cc/0x560 fs/buffer.c:1125
Code: c0 8b 48 89 df e8 04 43 bc ff 90 0f 0b e8 4c 7f 74 ff 48 c7 c6 e0 49 c0 8b 48 89 df e8 ed 42 bc ff 90 0f 0b e8 35 7f 74 ff 90 <0f> 0b 90 8b 74 24 0c 89 ea 48 c7 c7 40 4b c0 8b 31 db e8 4d 92 53
RSP: 0018:ffffc90003a3f7f0 EFLAGS: 00010293

RAX: 0000000000000000 RBX: 0000000000000200 RCX: ffffffff824775a6
RDX: ffff88802d388000 RSI: ffffffff824779eb RDI: 0000000000000005
RBP: 0000000000000400 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000200 R11: 0000000000000001 R12: ffff8880240db980
R13: 0000000000000100 R14: 0000000000000200 R15: ffff8880240db980
FS:  00007fc5345f26c0(0000) GS:ffff8881247f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000004a00 CR3: 00000000638a0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 bdev_getblk+0xd4/0xe0 fs/buffer.c:1461
 __bread_gfp+0x86/0x3c0 fs/buffer.c:1515
 sb_bread include/linux/buffer_head.h:346 [inline]
 udf_read_tagged+0xae/0x740 fs/udf/misc.c:199
 udf_check_anchor_block+0x89/0x4b0 fs/udf/super.c:1912
 udf_scan_anchors fs/udf/super.c:1952 [inline]
 udf_load_vrs+0x3b8/0x1070 fs/udf/super.c:2033
 udf_fill_super+0x791/0x1df0 fs/udf/super.c:2201
 get_tree_bdev_flags+0x389/0x620 fs/super.c:1692
 vfs_get_tree+0x8e/0x340 fs/super.c:1815
 do_new_mount fs/namespace.c:3805 [inline]
 path_mount+0x1482/0x1fd0 fs/namespace.c:4120
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount fs/namespace.c:4321 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4321
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc53378e9a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc5345f2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc5339b5fa0 RCX: 00007fc53378e9a9
RDX: 0000200000000080 RSI: 0000200000004a00 RDI: 0000200000000000
RBP: 00007fc533810d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000014 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc5339b5fa0 R15: 00007ffcecbba4c8
 </TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@...glegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup