--- libmpdemux/demux_mov.c
+++ libmpdemux/demux_mov.c
@@ -56,6 +56,11 @@
 #define char2short(x,y)	BE_16(&(x)[(y)])
 #define char2int(x,y) 	BE_32(&(x)[(y)])
 
+#ifndef FFMAX
+#define FFMAX(a,b) ((a) > (b) ? (a) : (b))
+#define FFMIN(a,b) ((a) > (b) ? (b) : (a))
+#endif /* FFMAX */
+
 typedef struct {
     unsigned int pts; // duration
     unsigned int size;
@@ -163,11 +166,12 @@ void mov_build_index(mov_track_t* trak,int timescale){
     i=trak->chunkmap_size;
     while(i>0){
 	--i;
-	for(j=trak->chunkmap[i].first;j<last;j++){
+	j=FFMAX(trak->chunkmap[i].first, 0);
+	for(;j<last;j++){
 	    trak->chunks[j].desc=trak->chunkmap[i].sdid;
 	    trak->chunks[j].size=trak->chunkmap[i].spc;
 	}
-	last=trak->chunkmap[i].first;
+	last=FFMIN(trak->chunkmap[i].first, trak->chunks_size);
     }
 
 #if 0
@@ -209,6 +213,8 @@ void mov_build_index(mov_track_t* trak,int timescale){
     s=0;
     for(j=0;j<trak->durmap_size;j++){
 	for(i=0;i<trak->durmap[j].num;i++){
+	    if (s >= trak->samples_size)
+		break;
 	    trak->samples[s].pts=pts;
 	    ++s;
 	    pts+=trak->durmap[j].dur;
@@ -220,6 +226,8 @@ void mov_build_index(mov_track_t* trak,int timescale){
     for(j=0;j<trak->chunks_size;j++){
 	off_t pos=trak->chunks[j].pos;
 	for(i=0;i<trak->chunks[j].size;i++){
+	    if (s >= trak->samples_size)
+		break;
 	    trak->samples[s].pos=pos;
 	    mp_msg(MSGT_DEMUX, MSGL_DBG3, "Sample %5d: pts=%8d  off=0x%08X  size=%d\n",s,
 		trak->samples[s].pts,
@@ -1454,8 +1462,7 @@ static void lschunks(demuxer_t* demuxer,int level,off_t endpos,mov_track_t* trak
 			if( udta_len>udta_size)
 				udta_len=udta_size;
 			{
-			char dump[udta_len-4];
-			stream_read(demuxer->stream, (char *)&dump, udta_len-4-4);
+			stream_skip(demuxer->stream, udta_len-4-4);
 			udta_size -= udta_len;
 			}
 		    }