ocfs2: replace simple_strtoull() with kstrtoull()

simple_strtoull() is deprecated in some situation since it does not check
for the range overflow, use kstrtoull() instead.

Link: https://lkml.kernel.org/r/20210526092020.554341-3-chenhuang5@huawei.comSigned-off-by: Chen Huang <chenhuang5@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/cluster/heartbeat.c

@@ -1596,12 +1596,13 @@ static ssize_t o2hb_region_start_block_store(struct config_item *item,
 	struct o2hb_region *reg = to_o2hb_region(item);
 	unsigned long long tmp;
 	char *p = (char *)page;
+	ssize_t ret;
 
 	if (reg->hr_bdev)
 		return -EINVAL;
 
-	tmp = simple_strtoull(p, &p, 0);
-	if (!p || (*p && (*p != '\n')))
+	ret = kstrtoull(p, 0, &tmp);
+	if (ret)
 		return -EINVAL;
 
 	reg->hr_start_block = tmp;