[syzbot] [udf?] UBSAN: array-index-out-of-bounds in udf_process_sequence

From: syzbot
Date: Mon Jul 31 2023 - 15:39:57 EST


Hello,

syzbot found the following issue on:

HEAD commit: 0a8db05b571a Merge tag 'platform-drivers-x86-v6.5-3' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=145f2726a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=5d10d93e1ae1f229
dashboard link: https://syzkaller.appspot.com/bug?extid=abb7222a58e4ebc930ad
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/58a518a693f4/disk-0a8db05b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/22cc85e51a4d/vmlinux-0a8db05b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/daeac90304b9/bzImage-0a8db05b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+abb7222a58e4ebc930ad@xxxxxxxxxxxxxxxxxxxxxxxxx

================================================================================
UBSAN: array-index-out-of-bounds in fs/udf/super.c:1365:9
index 4 is out of range for type '__le32[4]' (aka 'unsigned int[4]')
CPU: 0 PID: 10089 Comm: syz-executor.0 Not tainted 6.5.0-rc3-syzkaller-00044-g0a8db05b571a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:217 [inline]
__ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
udf_load_sparable_map fs/udf/super.c:1365 [inline]
udf_load_logicalvol fs/udf/super.c:1457 [inline]
udf_process_sequence+0x300d/0x4e70 fs/udf/super.c:1773
udf_load_sequence fs/udf/super.c:1820 [inline]
udf_check_anchor_block+0x2a6/0x550 fs/udf/super.c:1855
udf_scan_anchors fs/udf/super.c:1909 [inline]
udf_load_vrs+0xa71/0x1100 fs/udf/super.c:1969
udf_fill_super+0x95d/0x23a0 fs/udf/super.c:2147
mount_bdev+0x276/0x3b0 fs/super.c:1391
legacy_get_tree+0xef/0x190 fs/fs_context.c:611
vfs_get_tree+0x8c/0x270 fs/super.c:1519
do_new_mount+0x28f/0xae0 fs/namespace.c:3335
do_mount fs/namespace.c:3675 [inline]
__do_sys_mount fs/namespace.c:3884 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f838747e22a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f838819eee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f838819ef80 RCX: 00007f838747e22a
RDX: 0000000020000100 RSI: 0000000020000200 RDI: 00007f838819ef40
RBP: 0000000020000100 R08: 00007f838819ef80 R09: 0000000000214856
R10: 0000000000214856 R11: 0000000000000202 R12: 0000000020000200
R13: 00007f838819ef40 R14: 0000000000000c1d R15: 0000000020000240
</TASK>
================================================================================


---
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