fs: dlm: add errno handling to check callback

stable inclusion
from stable-5.10.38
commit ca973d2aeaf70c15e6663be3f71ba1b17a127051
bugzilla: 51875
CVE: NA

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

[ Upstream commit 8aa9540b ]

This allows to return individual errno values for the config attribute
check callback instead of returning invalid argument only.
Signed-off-by: NAlexander Aring <aahringo@redhat.com>
Signed-off-by: NDavid Teigland <teigland@redhat.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

fs/dlm/config.c

@@ -125,7 +125,7 @@ static ssize_t cluster_cluster_name_store(struct config_item *item,
 CONFIGFS_ATTR(cluster_, cluster_name);
 
 static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
-			   int *info_field, bool (*check_cb)(unsigned int x),
+			   int *info_field, int (*check_cb)(unsigned int x),
 			   const char *buf, size_t len)
 {
 	unsigned int x;
@@ -137,8 +137,11 @@ static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
 	if (rc)
 		return rc;
 
-	if (check_cb && check_cb(x))
-		return -EINVAL;
+	if (check_cb) {
+		rc = check_cb(x);
+		if (rc)
+			return rc;
+	}
 
 	*cl_field = x;
 	*info_field = x;
@@ -161,14 +164,20 @@ static ssize_t cluster_##name##_show(struct config_item *item, char *buf)     \
 }                                                                             \
 CONFIGFS_ATTR(cluster_, name);
 
-static bool dlm_check_zero(unsigned int x)
+static int dlm_check_zero(unsigned int x)
 {
-	return !x;
+	if (!x)
+		return -EINVAL;
+
+	return 0;
 }
 
-static bool dlm_check_buffer_size(unsigned int x)
+static int dlm_check_buffer_size(unsigned int x)
 {
-	return (x < DEFAULT_BUFFER_SIZE);
+	if (x < DEFAULT_BUFFER_SIZE)
+		return -EINVAL;
+
+	return 0;
 }
 
 CLUSTER_ATTR(tcp_port, dlm_check_zero);