diff --git a/src/smf_load.c b/src/smf_load.c
index 7389654..84f7221 100644
--- a/src/smf_load.c
+++ b/src/smf_load.c
@@ -283,7 +283,7 @@ expected_sysex_length(const unsigned char status, const unsigned char *second_by
 {
 	int sysex_length, len;
 
-	assert(status == 0xF0);
+	assert(status == 0xF0 || status == 0xF7);
 
 	if (buffer_length < 3) {
 		g_critical("SMF error: end of buffer in expected_sysex_length().");
@@ -441,7 +441,7 @@ extract_escaped_event(const unsigned char *buf, const int buffer_length, smf_eve
 
 	message_length = expected_escaped_length(status, c, buffer_length - 1, &vlq_length);
 
-	if (message_length < 0)
+	if (message_length <= 0)
 		return (-3);
 
 	c += vlq_length;
@@ -460,12 +460,12 @@ extract_escaped_event(const unsigned char *buf, const int buffer_length, smf_eve
 
 	memcpy(event->midi_buffer, c, message_length);
 
-	if (smf_event_is_valid(event)) {
+	if (!smf_event_is_valid(event)) {
 		g_critical("Escaped event is invalid.");
 		return (-1);
 	}
 
-	if (smf_event_is_system_realtime(event) || smf_event_is_system_common(event)) {
+	if (!(smf_event_is_system_realtime(event) || smf_event_is_system_common(event))) {
 		g_warning("Escaped event is not System Realtime nor System Common.");
 	}
 
@@ -503,11 +503,21 @@ extract_midi_event(const unsigned char *buf, const int buffer_length, smf_event_
 		return (-1);
 	}
 
-	if (is_sysex_byte(status))
+	if (is_sysex_byte(status)) {
+		if (c == buf) {
+			g_critical("SMF error: running status is not applicable to System Exclusive events.");
+			return (-2);
+		}
 		return (extract_sysex_event(buf, buffer_length, event, len, last_status));
+	}
 
-	if (is_escape_byte(status))
+	if (is_escape_byte(status)) {
+		if (c == buf) {
+			g_critical("SMF error: running status is not applicable to Escape events.");
+			return (-2);
+		}
 		return (extract_escaped_event(buf, buffer_length, event, len, last_status));
+	}
 
 	/* At this point, "c" points to first byte following the status byte. */
 	message_length = expected_message_length(status, c, buffer_length - (c - buf));
@@ -768,12 +778,23 @@ smf_event_is_valid(const smf_event_t *event)
 static int
 parse_mtrk_chunk(smf_track_t *track)
 {
+	smf_t *smf = track->smf;
 	smf_event_t *event;
 
 	if (parse_mtrk_header(track))
 		return (-1);
 
+	if (track->file_buffer + track->file_buffer_length > smf->file_buffer + smf->file_buffer_length) {
+		/* Truncated track? */
+		track->file_buffer_length = smf->file_buffer_length - (track->file_buffer - smf->file_buffer);
+	}
+
 	for (;;) {
+		if (track->next_event_offset == track->file_buffer_length) {
+			g_warning("SMF warning: The track did not finish with the End of Track event.");
+			break;
+		}
+
 		event = parse_next_event(track);
 
 		/* Couldn't parse an event? */
@@ -869,13 +890,17 @@ smf_load_from_memory(const void *buffer, const int buffer_length)
 	smf->file_buffer_length = buffer_length;
 	smf->next_chunk_offset = 0;
 
-	if (parse_mthd_chunk(smf))
+	if (parse_mthd_chunk(smf)) {
+		smf_delete(smf);
 		return (NULL);
+        }
 
 	for (i = 1; i <= smf->expected_number_of_tracks; i++) {
 		smf_track_t *track = smf_track_new();
-		if (track == NULL)
+		if (track == NULL) {
+			smf_delete(smf);
 			return (NULL);
+		}
 
 		smf_add_track(smf, track);
 
@@ -883,6 +908,7 @@ smf_load_from_memory(const void *buffer, const int buffer_length)
 		if (parse_mtrk_chunk(track)) {
 			g_warning("SMF warning: Cannot load track.");
 			smf_track_delete(track);
+			break;
 		}
 
 		track->file_buffer = NULL;
diff --git a/src/smf_tempo.c b/src/smf_tempo.c
index a5592f1..d9a4df9 100644
--- a/src/smf_tempo.c
+++ b/src/smf_tempo.c
@@ -133,6 +133,11 @@ maybe_add_to_tempo_map(smf_event_t *event)
 
 	/* Tempo Change? */
 	if (event->midi_buffer[1] == 0x51) {
+		if (event->midi_buffer_length < 6) {
+			g_critical("Tempo Change event seems truncated.");
+			return;
+		}
+
 		int new_tempo = (event->midi_buffer[3] << 16) + (event->midi_buffer[4] << 8) + event->midi_buffer[5];
 		if (new_tempo <= 0) {
 			g_critical("Ignoring invalid tempo change.");