linux-kernel - [syzbot] [squashfs?] UBSAN: shift-out-of-bounds in squashfs_bio

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Message-ID: <67f0dd7a.050a0220.0a13.0230.GAE@google.com>
Date: Sat, 05 Apr 2025 00:36:26 -0700
From: syzbot <syzbot+65761fc25a137b9c8c6e@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org, phillip@...ashfs.org.uk, 
	squashfs-devel@...ts.sourceforge.net, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [squashfs?] UBSAN: shift-out-of-bounds in squashfs_bio_read

Hello,

syzbot found the following issue on:

HEAD commit:    609706855d90 Merge tag 'trace-latency-v6.15-3' of git://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a88fb0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f8721be6a767792
dashboard link: https://syzkaller.appspot.com/bug?extid=65761fc25a137b9c8c6e
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/48bd65025d89/disk-60970685.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/332202d68035/vmlinux-60970685.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1c4aa49d3e14/bzImage-60970685.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65761fc25a137b9c8c6e@...kaller.appspotmail.com

loop0: detected capacity change from 0 to 8
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/squashfs/block.c:195:36
shift exponent 64 is too large for 64-bit type 'u64' (aka 'unsigned long long')
CPU: 0 UID: 0 PID: 6373 Comm: syz.0.109 Not tainted 6.14.0-syzkaller-11125-g609706855d90 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:492
 squashfs_bio_read+0x1050/0x1180 fs/squashfs/block.c:195
 squashfs_read_data+0x2e7/0xba0 fs/squashfs/block.c:333
 squashfs_read_table+0x338/0x390 fs/squashfs/cache.c:436
 squashfs_fill_super+0x238/0x21e0 fs/squashfs/super.c:216
 get_tree_bdev_flags+0x492/0x5c0 fs/super.c:1636
 vfs_get_tree+0x92/0x2b0 fs/super.c:1759
 do_new_mount+0x2cf/0xb70 fs/namespace.c:3878
 do_mount fs/namespace.c:4218 [inline]
 __do_sys_mount fs/namespace.c:4429 [inline]
 __se_sys_mount+0x38c/0x400 fs/namespace.c:4406
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f229398e90a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2294866e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f2294866ef0 RCX: 00007f229398e90a
RDX: 0000200000000040 RSI: 0000200000000240 RDI: 00007f2294866eb0
RBP: 0000200000000040 R08: 00007f2294866ef0 R09: 0000000000210c00
R10: 0000000000210c00 R11: 0000000000000246 R12: 0000200000000240
R13: 00007f2294866eb0 R14: 00000000000001ad R15: 0000200000001480
 </TASK>
---[ end trace ]---


---
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