ocfs2: fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()

This patch addresses a shift-out-of-bounds error in the
ocfs2_verify_volume() function, identified by UBSAN.  The bug was
triggered by an invalid s_clustersize_bits value (e.g., 1548), which
caused the expression "1 <<
le32_to_cpu(di->id2.i_super.s_clustersize_bits)" to exceed the limits of a
32-bit integer, leading to an out-of-bounds shift.

Link: https://lkml.kernel.org/r/ZsPvwQAXd5R/jNY+@hostname
Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
qasdev 2024-08-20 02:22:09 +01:00 committed by Andrew Morton
parent d994c23834
commit 7f86b29427

View File

@ -2357,8 +2357,8 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
(unsigned long long)bh->b_blocknr);
} else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
mlog(ML_ERROR, "bad cluster size found: %u\n",
1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
mlog(ML_ERROR, "bad cluster size bit found: %u\n",
le32_to_cpu(di->id2.i_super.s_clustersize_bits));
} else if (!le64_to_cpu(di->id2.i_super.s_root_blkno)) {
mlog(ML_ERROR, "bad root_blkno: 0\n");
} else if (!le64_to_cpu(di->id2.i_super.s_system_dir_blkno)) {