From: qasdev <qasdev00@gmail.com>
Date: Tue, 20 Aug 2024 01:22:09 +0000 (+0100)
Subject: ocfs2: fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()
X-Git-Tag: v6.12-rc1~114^2~36
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7f86b2942791012ac7b4c481d1f84a58fd2fbcfc;p=thirdparty%2Fkernel%2Flinux.git

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>
---

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index afee70125ae3b..b704983b21120 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -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)) {