diff -Naurp a/source3/modules/vfs_streams_xattr.c b/source3/modules/vfs_streams_xattr.c
index 03ff6147cb0..4fb4f42baa0 100644
--- a/source3/modules/vfs_streams_xattr.c
+++ b/source3/modules/vfs_streams_xattr.c
@@ -959,14 +959,17 @@ static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle,
 
         if ((offset + n) > ea.value.length - config->xattr_compat_bytes) {
 		uint8_t *tmp;
+		size_t new_sz = offset + n + config->xattr_compat_bytes;
 
 		tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8_t,
-					   offset + n + config->xattr_compat_bytes);
+					   new_sz);
 
 		if (tmp == NULL) {
 			TALLOC_FREE(ea.value.data);
                         errno = ENOMEM;
                         return -1;
                 }
+
+		memset(tmp + ea.value.length, 0, new_sz - ea.value.length);
 		ea.value.data = tmp;
- 		ea.value.length = offset + n + config->xattr_compat_bytes;
+ 		ea.value.length = new_sz;
		if (config->xattr_compat_bytes) {

diff -Naurp a/source4/nbt_server/wins/wins_hook.c b/source4/nbt_server/wins/wins_hook.c
index 1af471b15bc..442141fecdd 100644
--- a/source4/nbt_server/wins/wins_hook.c
+++ b/source4/nbt_server/wins/wins_hook.c
@@ -43,9 +43,18 @@ void wins_hook(struct winsdb_handle *h, const struct winsdb_record *rec,
 	int child;
 	char *cmd = NULL;
 	TALLOC_CTX *tmp_mem = NULL;
+	const char *p = NULL;
 
 	if (!wins_hook_script || !wins_hook_script[0]) return;
 
+	for (p = rec->name->name; *p; p++) {
+		if (!(isalnum((int)*p) || strchr_m("._-", *p))) {
+			DBG_ERR("not calling wins hook for invalid name %s\n",
+				rec->name->name);
+			return;
+		}
+	}
+
 	tmp_mem = talloc_new(h);
 	if (!tmp_mem) goto failed;