[syzbot] [jfs?] UBSAN: shift-out-of-bounds in jfs_statfs (2)

From: syzbot
Date: Sun Sep 15 2024 - 19:58:36 EST


Hello,

syzbot found the following issue on:

HEAD commit: 7c6a3a65ace7 minmax: reduce min/max macro expansion in ato..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15105807980000
kernel config: https://syzkaller.appspot.com/x/.config?x=1c9e296880039df9
dashboard link: https://syzkaller.appspot.com/bug?extid=bb0aa125eb8d70475ebd
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/06208dec0174/disk-7c6a3a65.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bd09f189e9df/vmlinux-7c6a3a65.xz
kernel image: https://storage.googleapis.com/syzbot-assets/25e56ca1462d/bzImage-7c6a3a65.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bb0aa125eb8d70475ebd@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/jfs/super.c:140:14
shift exponent 770 is too large for 64-bit type 's64' (aka 'long long')
CPU: 0 UID: 0 PID: 8224 Comm: syz.2.276 Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
jfs_statfs+0x503/0x510 fs/jfs/super.c:140
statfs_by_dentry fs/statfs.c:66 [inline]
vfs_statfs+0x13b/0x2c0 fs/statfs.c:90
ovl_check_namelen fs/overlayfs/super.c:375 [inline]
ovl_lower_dir fs/overlayfs/super.c:391 [inline]
ovl_get_lowerstack fs/overlayfs/super.c:1132 [inline]
ovl_fill_super+0x8ed/0x3560 fs/overlayfs/super.c:1392
vfs_get_super fs/super.c:1280 [inline]
get_tree_nodev+0xb7/0x140 fs/super.c:1299
vfs_get_tree+0x90/0x2b0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3472
do_mount fs/namespace.c:3812 [inline]
__do_sys_mount fs/namespace.c:4020 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54f4d7def9
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:00007f54f5b25038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f54f4f35f80 RCX: 00007f54f4d7def9
RDX: 0000000020000180 RSI: 0000000020000140 RDI: 0000000000000000
RBP: 00007f54f4df0b76 R08: 00000000200001c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f54f4f35f80 R15: 00007fff0587cfb8
</TASK>
---[ end trace ]---


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