[syzbot] [jfs?] UBSAN: array-index-out-of-bounds in dbNextAG (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    22f902dfc51e Merge tag 'i2c-for-6.10-rc7' of git://git.ker..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=175c1059980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1ace69f521989b1f
dashboard link: https://syzkaller.appspot.com/bug?extid=808f3f84407f08a93022
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17eb06e1980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16e6f6e1980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/da00a62c06a3/disk-22f902df.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e090db7ab1fa/vmlinux-22f902df.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5332f53497de/bzImage-22f902df.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/ec0f0006ae2c/mount_0.gz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15d45c9e980000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=17d45c9e980000
console output: https://syzkaller.appspot.com/x/log.txt?x=13d45c9e980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+808f3f84407f08a93022@xxxxxxxxxxxxxxxxxxxxxxxxx

loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:661:7
index 128 is out of range for type 's64[128]' (aka 'long long[128]')
CPU: 0 PID: 5083 Comm: syz-executor157 Not tainted 6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:429
 dbNextAG+0x3f3/0x630 fs/jfs/jfs_dmap.c:661
 diAlloc+0x6c6/0x1760 fs/jfs/jfs_imap.c:1369
 ialloc+0x8f/0x900 fs/jfs/jfs_inode.c:56
 jfs_create+0x1be/0xb90 fs/jfs/namei.c:92
 lookup_open fs/namei.c:3505 [inline]
 open_last_lookups fs/namei.c:3574 [inline]
 path_openat+0x1a84/0x35f0 fs/namei.c:3810
 do_filp_open+0x235/0x490 fs/namei.c:3840
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1413
 do_sys_open fs/open.c:1428 [inline]
 __do_sys_openat fs/open.c:1444 [inline]
 __se_sys_openat fs/open.c:1439 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1439
 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: 0033:0x7fdb9c0a0a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffecc111738 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdb9c0a0a99
RDX: 000000000000275a RSI: 00000000200005c0 RDI: 00000000ffffff9c
RBP: 00007fdb9c11a5f0 R08: 000055555c2c14c0 R09: 000055555c2c14c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffecc111760
R13: 00007ffecc111988 R14: 431bde82d7b634db R15: 00007fdb9c0e903b
 </TASK>
---[ end trace ]---


---
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