[PATCH v2] ocfs2: heartbeat: replace simple_strtoul with kstrtoul

[Daniel Yang]

The function simple_strtoul is deprecated due to ignoring overflows and
also requires clunkier error checking. Replacing with kstrtoul() leads
to safer code and cleaner error checking.

Signed-off-by: Daniel Yang <danielyangkang@xxxxxxxxx>
---
v1->v2: moved ret definition and removed blank lines

 fs/ocfs2/cluster/heartbeat.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index dff18efbc..84ee5e340 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1536,9 +1536,8 @@ static int o2hb_read_block_input(struct o2hb_region *reg,
 {
 	unsigned long bytes;
 	char *p = (char *)page;
-
-	bytes = simple_strtoul(p, &p, 0);
-	if (!p || (*p && (*p != '\n')))
+	int ret = kstrtoul(p, 0, &bytes);
+	if (ret)
 		return -EINVAL;
 
 	/* Heartbeat and fs min / max block sizes are the same. */
@@ -1623,12 +1622,13 @@ static ssize_t o2hb_region_blocks_store(struct config_item *item,
 	struct o2hb_region *reg = to_o2hb_region(item);
 	unsigned long tmp;
 	char *p = (char *)page;
+	int ret;
 
 	if (reg->hr_bdev_file)
 		return -EINVAL;
 
-	tmp = simple_strtoul(p, &p, 0);
-	if (!p || (*p && (*p != '\n')))
+	ret = kstrtoul(p, 0, &tmp);
+	if (ret)
 		return -EINVAL;
 
 	if (tmp > O2NM_MAX_NODES || tmp == 0)
@@ -2141,9 +2141,8 @@ static ssize_t o2hb_heartbeat_group_dead_threshold_store(struct config_item *ite
 {
 	unsigned long tmp;
 	char *p = (char *)page;
-
-	tmp = simple_strtoul(p, &p, 10);
-	if (!p || (*p && (*p != '\n')))
+	int ret = kstrtoul(p, 10, &tmp);
+	if (ret)
                 return -EINVAL;
 
 	/* this will validate ranges for us. */
-- 
2.39.5