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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    9221b2819b8a Add linux-next specific files for 20240503
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14631754980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8ab537f51a6a0d98
dashboard link: https://syzkaller.appspot.com/bug?extid=13e8cd4926977f8337b6
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=15123b1f180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16b7da2f180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e67dbdc3c37/disk-9221b281.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ade618fa19f8/vmlinux-9221b281.xz
kernel image: https://storage.googleapis.com/syzbot-assets/df12e5073c97/bzImage-9221b281.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/41dea5c977c2/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+13e8cd4926977f8337b6@xxxxxxxxxxxxxxxxxxxxxxxxx

loop0: detected capacity change from 0 to 32768
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/jfs/jfs_extent.c:319:16
shift exponent 108 is too large for 64-bit type 's64' (aka 'long long')
CPU: 0 PID: 5090 Comm: syz-executor421 Not tainted 6.9.0-rc6-next-20240503-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 extBalloc fs/jfs/jfs_extent.c:319 [inline]
 extAlloc+0xe5c/0x1010 fs/jfs/jfs_extent.c:122
 jfs_get_block+0x41b/0xe60 fs/jfs/inode.c:248
 __block_write_begin_int+0x50c/0x1a70 fs/buffer.c:2128
 __block_write_begin fs/buffer.c:2177 [inline]
 block_write_begin+0x9b/0x1e0 fs/buffer.c:2236
 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299
 generic_perform_write+0x322/0x640 mm/filemap.c:4016
 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4137
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d15f6f639
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 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:00007fff3dae85f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fff3dae87c8 RCX: 00007f4d15f6f639
RDX: 00000000fffffef2 RSI: 0000000020000240 RDI: 0000000000000004
RBP: 00007f4d15fe8610 R08: 0000000000000000 R09: 00007fff3dae87c8
R10: 0000000000006162 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff3dae87b8 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
---[ end trace ]---


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