diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 86480e5a215e..c235f9a60394 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -431,6 +431,8 @@ static int ceph_parse_mount_param(struct fs_context *fc,
 
 	switch (token) {
 	case Opt_snapdirname:
+		if (strlen(param->string) > NAME_MAX)
+			return invalfc(fc, "snapdirname too long");
 		kfree(fsopt->snapdir_name);
 		fsopt->snapdir_name = param->string;
 		param->string = NULL;