[PATCH] ocfs2: heartbeat: replace simple_strtoul with kstrtoul

[Daniel Yang <danielyangkang@gmail.com>]

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@gmail.com>
---
 fs/ocfs2/cluster/heartbeat.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index dff18efbc..4fc1b23f1 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1537,8 +1537,9 @@ 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. */
@@ -1627,8 +1628,9 @@ static ssize_t o2hb_region_blocks_store(struct config_item *item,
 	if (reg->hr_bdev_file)
 		return -EINVAL;
 
-	tmp = simple_strtoul(p, &p, 0);
-	if (!p || (*p && (*p != '\n')))
+	int ret = kstrtoul(p, 0, &tmp);
+
+	if (ret)
 		return -EINVAL;
 
 	if (tmp > O2NM_MAX_NODES || tmp == 0)
@@ -2142,8 +2144,9 @@ 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