client: Fix crash that occured when receiving client command from old client

1 files changed, 5 insertions, 0 deletions

diff --git a/src/client.c b/src/client.c
index c6a7ce8..b30fb06 100644
--- a/src/client.c
+++ b/src/client.c
@@ -476,6 +476,11 @@ static int client_command(struct mux_client *client, struct usbmuxd_header *hdr)
                         } else {
                                 char *message = NULL;
                                 plist_t node = plist_dict_get_item(dict, "MessageType");
+                                if (!node || plist_get_node_type(node) != PLIST_STRING) {
+                                        usbmuxd_log(LL_ERROR, "Could not read valid MessageType node from plist!");
+                                        plist_free(dict);
+                                        return -1;
+                                }
                                 plist_get_string_val(node, &message);
                                 if (!message) {
                                         usbmuxd_log(LL_ERROR, "Could not extract MessageType from plist!");