ext4: make variable "count" signed

stable inclusion
from stable-4.19.249
commit c86fce1d8c083d268103d2d19e5a9a66000a8e6f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5I4FP
CVE: NA

--------------------------------

commit bc75a6eb upstream.

Since dx_make_map() may return -EFSCORRUPTED now, so change "count" to
be a signed integer so we can correctly check for an error code returned
by dx_make_map().

Fixes: 46c116b9 ("ext4: verify dir block before splitting it")
Cc: stable@kernel.org
Signed-off-by: NDing Xiang <dingxiang@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20220530100047.537598-1-dingxiang@cmss.chinamobile.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

fs/ext4/namei.c

@@ -1719,7 +1719,8 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
 			struct dx_hash_info *hinfo)
 {
 	unsigned blocksize = dir->i_sb->s_blocksize;
-	unsigned count, continued;
+	unsigned continued;
+	int count;
 	struct buffer_head *bh2;
 	ext4_lblk_t newblock;
 	u32 hash2;