[v6.6] WARNING in __udf_add_aext

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dbcb8d8e4163 Linux 6.6.100
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=154a2ca2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=293251cfa8d8100
dashboard link: https://syzkaller.appspot.com/bug?extid=7e3876c1d0bf0b7e3895
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d0b56817a2c3/disk-dbcb8d8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0d646b2f7fa/vmlinux-dbcb8d8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e0b752a5011/bzImage-dbcb8d8e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7e3876...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 2048
UDF-fs: INFO Mounting volume 'Li uxUDF', timestamp 2022/11/22 14:59 (1000)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 6812 at fs/udf/inode.c:2081 __udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Modules linked in:
CPU: 0 PID: 6812 Comm: syz.0.224 Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Code: 08 4c 89 f7 e8 53 71 e7 fe 49 8b 3e 4c 89 e6 e8 68 27 06 ff 31 c0 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 32 2b 90 fe <0f> 0b e9 1b fc ff ff e8 26 2b 90 fe 0f 0b e9 6f fd ff ff e8 1a 2b
RSP: 0018:ffffc9001914f4a0 EFLAGS: 00010283
RAX: ffffffff82f56a4e RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9000c769000 RSI: 0000000000038d00 RDI: 0000000000038d01
RBP: 1ffff92003229ecf R08: ffff88801f2d0000 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000004 R14: ffffc9001914f670 R15: ffffc9001914f678
FS: 00007f67a94316c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000a080 CR3: 00000000267a8000 CR4: 00000000003506f0
Call Trace:
<TASK>
udf_add_aext fs/udf/inode.c:2138 [inline]
udf_insert_aext fs/udf/inode.c:2317 [inline]
udf_update_extents fs/udf/inode.c:1209 [inline]
inode_getblk fs/udf/inode.c:923 [inline]
udf_map_block+0x352d/0x4500 fs/udf/inode.c:451
__udf_get_block+0x53/0x250 fs/udf/inode.c:465
__block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124
__block_write_begin fs/buffer.c:2173 [inline]
block_write_begin+0x9a/0x1e0 fs/buffer.c:2234
udf_write_begin+0x1c0/0x430 fs/udf/inode.c:261
generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4016
udf_file_write_iter+0x2c0/0x620 fs/udf/file.c:111
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f67a858e9a9
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:00007f67a9431038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f67a87b5fa0 RCX: 00007f67a858e9a9
RDX: 0000000000000035 RSI: 000020000000a080 RDI: 0000000000000004
RBP: 00007f67a8610d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f67a87b5fa0 R15: 00007ffff721d3d8
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: dbcb8d8e4163 Linux 6.6.100
git tree: linux-6.6.y

console output: https://syzkaller.appspot.com/x/log.txt?x=123c2cf0580000

kernel config: https://syzkaller.appspot.com/x/.config?x=293251cfa8d8100
dashboard link: https://syzkaller.appspot.com/bug?extid=7e3876c1d0bf0b7e3895
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11698ca2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13d12ca2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d0b56817a2c3/disk-dbcb8d8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0d646b2f7fa/vmlinux-dbcb8d8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e0b752a5011/bzImage-dbcb8d8e.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/605fd378b155/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7e3876...@syzkaller.appspotmail.com

syz.0.16[5943]: memfd_create() called without MFD_EXEC or MFD_NOEXEC_SEAL set

loop0: detected capacity change from 0 to 2048
UDF-fs: INFO Mounting volume 'Li uxUDF', timestamp 2022/11/22 14:59 (1000)
------------[ cut here ]------------

WARNING: CPU: 0 PID: 5943 at fs/udf/inode.c:2081 __udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Modules linked in:
CPU: 0 PID: 5943 Comm: syz.0.16 Not tainted 6.6.100-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Code: 08 4c 89 f7 e8 53 71 e7 fe 49 8b 3e 4c 89 e6 e8 68 27 06 ff 31 c0 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 32 2b 90 fe <0f> 0b e9 1b fc ff ff e8 26 2b 90 fe 0f 0b e9 6f fd ff ff e8 1a 2b

RSP: 0018:ffffc900030474a0 EFLAGS: 00010293
RAX: ffffffff82f56a4e RBX: dffffc0000000000 RCX: ffff88802b23bc00
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: 1ffff92000608ecf R08: ffff88802b23bc00 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000004 R14: ffffc90003047670 R15: ffffc90003047678
FS: 00005555587b5500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000020000000a080 CR3: 0000000025513000 CR4: 00000000003506f0

Call Trace:
<TASK>
udf_add_aext fs/udf/inode.c:2138 [inline]
udf_insert_aext fs/udf/inode.c:2317 [inline]
udf_update_extents fs/udf/inode.c:1209 [inline]
inode_getblk fs/udf/inode.c:923 [inline]
udf_map_block+0x352d/0x4500 fs/udf/inode.c:451
__udf_get_block+0x53/0x250 fs/udf/inode.c:465
__block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124
__block_write_begin fs/buffer.c:2173 [inline]
block_write_begin+0x9a/0x1e0 fs/buffer.c:2234
udf_write_begin+0x1c0/0x430 fs/udf/inode.c:261
generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4016
udf_file_write_iter+0x2c0/0x620 fs/udf/file.c:111
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

RIP: 0033:0x7f18ea78e9a9

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:00007fff9abbd2b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f18ea9b5fa0 RCX: 00007f18ea78e9a9

RDX: 0000000000000035 RSI: 000020000000a080 RDI: 0000000000000004

RBP: 00007f18ea810d69 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007f18ea9b5fa0 R14: 00007f18ea9b5fa0 R15: 0000000000000003
</TASK>


---
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