[syzbot] UBSAN: shift-out-of-bounds in dbBackSplit

[syzbot] UBSAN: shift-out-of-bounds in dbBackSplit

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    61c3426aca2c Add linux-next specific files for 20221102
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1727cd46880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=acb529cc910d907c
dashboard link: https://syzkaller.appspot.com/bug?extid=3ef8947f8f9b50440df4
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14f170a9880000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12e2fff6880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/cc56d88dd6a3/disk-61c3426a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5921b65b080f/vmlinux-61c3426a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/39cbd355fedd/bzImage-61c3426a.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/de5204da8a03/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ef8947f8f9b50440df4@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
================================================================================
UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:2621:11
shift exponent 109 is too large for 32-bit type 'int'
CPU: 0 PID: 5234 Comm: syz-executor124 Not tainted 6.1.0-rc3-next-20221102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 ubsan_epilogue+0xb/0x50 lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x187 lib/ubsan.c:322
 dbBackSplit.cold-0x5/0xca
 dbAllocBits+0x14f/0x5f0 fs/jfs/jfs_dmap.c:2173
 dbAllocDmap+0x61/0x110 fs/jfs/jfs_dmap.c:2014
 dbAllocNear fs/jfs/jfs_dmap.c:1243 [inline]
 dbAlloc+0x78a/0xa70 fs/jfs/jfs_dmap.c:828
 diNewExt+0x724/0x1a10 fs/jfs/jfs_imap.c:2251
 diAllocExt fs/jfs/jfs_imap.c:1945 [inline]
 diAllocAG+0x15f1/0x2200 fs/jfs/jfs_imap.c:1662
 diAlloc+0x82d/0x1730 fs/jfs/jfs_imap.c:1583
 ialloc+0x89/0xaa0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x1f0/0xab0 fs/jfs/namei.c:225
 vfs_mkdir+0x489/0x740 fs/namei.c:4035
 do_mkdirat+0x277/0x2f0 fs/namei.c:4060
 __do_sys_mkdir fs/namei.c:4080 [inline]
 __se_sys_mkdir fs/namei.c:4078 [inline]
 __x64_sys_mkdir+0xf2/0x140 fs/namei.c:4078
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd3da355dc9
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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe6b87ad38 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd3da355dc9
RDX: 00007fd3da3142c3 RSI: 0000000000000000 RDI: 00000000200052c0
RBP: 00007fd3da315590 R08: 000055555709e2c0 R09: 0000000000000000
R10: 00007ffe6b87ac00 R11: 0000000000000246 R12: 00000000f8008000
R13: 0000000000000000 R14: 00080000000000fc R15: 0000000000000000
 </TASK>
================================================================================


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