Fix NULL as mount(2) syscall data parameter

Passing NULL for the mount data should not result in EINVAL. It should be treated as if an empty string were passed and succeed. Signed-off-by: Brian Behlendorf <[email protected]> Signed-off-by: Ned Bass <[email protected]> Issue openzfs#3771
YanyunGao · Sep 19, 2015 · e49552a · e49552a
1 parent 0d00e81
commit e49552a
Showing 1 changed file with 24 additions and 23 deletions.
diff --git a/module/zfs/zpl_super.c b/module/zfs/zpl_super.c
@@ -227,8 +227,7 @@ static const match_table_t zpl_tokens = {
 };
 
 static int
-zpl_parse_option(char *option, int token, substring_t *args,
-    zfs_mntopts_t *zmo, boolean_t isremount)
+zpl_parse_option(char *option, int token, substring_t *args, zfs_mntopts_t *zmo)
 {
 	switch (token) {
 	case TOKEN_RO:
@@ -318,32 +317,34 @@ zpl_parse_options(char *osname, char *mntopts, zfs_mntopts_t *zmo,
     boolean_t isremount)
 {
 	zfs_mntopts_t *tmp_zmo;
-	substring_t args[MAX_OPT_ARGS];
-	char *tmp_mntopts, *p;
-	int error, token;
-
-	if (mntopts == NULL)
-		return (-EINVAL);
+	int error;
 
 	tmp_zmo = zfs_mntopts_alloc();
 	tmp_zmo->z_osname = strdup(osname);
-	tmp_mntopts = strdup(mntopts);
-
-	while ((p = strsep(&tmp_mntopts, ",")) != NULL) {
-		if (!*p)
-			continue;
-
-		args[0].to = args[0].from = NULL;
-		token = match_token(p, zpl_tokens, args);
-		error = zpl_parse_option(p, token, args, tmp_zmo, isremount);
-		if (error) {
-			zfs_mntopts_free(tmp_zmo);
-			strfree(tmp_mntopts);
-			return (error);
+
+	if (mntopts) {
+		substring_t args[MAX_OPT_ARGS];
+		char *tmp_mntopts, *p;
+		int token;
+
+		tmp_mntopts = strdup(mntopts);
+
+		while ((p = strsep(&tmp_mntopts, ",")) != NULL) {
+			if (!*p)
+				continue;
+
+			args[0].to = args[0].from = NULL;
+			token = match_token(p, zpl_tokens, args);
+			error = zpl_parse_option(p, token, args, tmp_zmo);
+			if (error) {
+				zfs_mntopts_free(tmp_zmo);
+				strfree(tmp_mntopts);
+				return (error);
+			}
 		}
-	}
 
-	strfree(tmp_mntopts);
+		strfree(tmp_mntopts);
+	}
 
 	if (isremount == B_TRUE) {
 		if (zmo->z_osname)