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

From: syzbot
Date: Sun Oct 02 2022 - 07:18:43 EST


syzbot found the following issue on:

HEAD commit: ffb4d94b4314 Merge tag 'drm-fixes-2022-10-01' of git://ano..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15877ab8880000
kernel config: https://syzkaller.appspot.com/x/.config?x=ba0d23aa7e1ffaf5
dashboard link: https://syzkaller.appspot.com/bug?extid=f0e5eba3996857670c88
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b74f52232e47/disk-ffb4d94b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b09212ee600a/vmlinux-ffb4d94b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0e5eba3996857670c88@xxxxxxxxxxxxxxxxxxxxxxxxx

UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:1785:12
shift exponent 711030885 is too large for 64-bit type 'long long'
CPU: 0 PID: 29745 Comm: syz-executor.2 Not tainted 6.0.0-rc7-syzkaller-00220-gffb4d94b4314 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:151 [inline]
__ubsan_handle_shift_out_of_bounds+0x33d/0x3b0 lib/ubsan.c:322
dbAllocCtl+0x93d/0x970 fs/jfs/jfs_dmap.c:1785
dbAllocAG+0x28b/0x1100 fs/jfs/jfs_dmap.c:1334
dbAlloc+0x661/0xc90 fs/jfs/jfs_dmap.c:858
diNewIAG fs/jfs/jfs_imap.c:2500 [inline]
diAllocExt fs/jfs/jfs_imap.c:1898 [inline]
diAllocAG+0xaf6/0x1f80 fs/jfs/jfs_imap.c:1662
diAlloc+0x3dd/0x1700 fs/jfs/jfs_imap.c:1583
ialloc+0x8c/0xa80 fs/jfs/jfs_inode.c:56
jfs_mkdir+0x141/0xb00 fs/jfs/namei.c:225
vfs_mkdir+0x3b3/0x590 fs/namei.c:4013
do_mkdirat+0x279/0x550 fs/namei.c:4038
__do_sys_mkdirat fs/namei.c:4053 [inline]
__se_sys_mkdirat fs/namei.c:4051 [inline]
__x64_sys_mkdirat+0x85/0x90 fs/namei.c:4051
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
RIP: 0033:0x7fd56248a5a9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd563556168 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fd5625abf80 RCX: 00007fd56248a5a9
RDX: 0000000000000000 RSI: 0000000020000540 RDI: 0000000000000004
RBP: 00007fd5624e5580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd10304c1f R14: 00007fd563556300 R15: 0000000000022000

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