mss1: validate number of changeable palette entries

13 years ago · 15358ade15
parent 8f5d573a83
commit 15358ade15
1 changed files with 6 additions and 0 deletions
--- a/libavcodec/mss1.c
+++ b/libavcodec/mss1.c
@ -783,6 +783,12 @@ static av_cold int mss1_decode_init(AVCodecContext *avctx)
    av_log(avctx, AV_LOG_DEBUG, "Encoder version %d.%d\n",
           AV_RB32(avctx->extradata + 4), AV_RB32(avctx->extradata + 8));
    c->free_colours     = AV_RB32(avctx->extradata + 48);
+    if ((unsigned)c->free_colours > 256) {
+        av_log(avctx, AV_LOG_ERROR,
+               "Incorrect number of changeable palette entries: %d\n",
+               c->free_colours);
+        return AVERROR_INVALIDDATA;
+    }
    av_log(avctx, AV_LOG_DEBUG, "%d free colour(s)\n", c->free_colours);
    avctx->coded_width  = AV_RB32(avctx->extradata + 20);
    avctx->coded_height = AV_RB32(avctx->extradata + 24);