From 94aefb1932be882fd93f66cf790ceb19ff575c19 Mon Sep 17 00:00:00 2001 From: Luca Barbato Date: Sun, 9 Jun 2013 18:27:05 +0200 Subject: [PATCH] 4xm: do not overread the source buffer in decode_p_block Check for out of picture macroblocks before calling mcdc. Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind CC: libav-stable@libav.org --- libavcodec/4xm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/libavcodec/4xm.c b/libavcodec/4xm.c index a70be14..2554ba9 100644 --- a/libavcodec/4xm.c +++ b/libavcodec/4xm.c @@ -370,6 +370,10 @@ static int decode_p_block(FourXContext *f, uint16_t *dst, uint16_t *src, log2w, log2h, stride)) < 0) return ret; } else if (code == 3 && f->version < 2) { + if (start > src || src > end) { + av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n"); + return AVERROR_INVALIDDATA; + } mcdc(dst, src, log2w, h, stride, 1, 0); } else if (code == 4) { src += f->mv[bytestream2_get_byte(&f->g)]; @@ -379,6 +383,10 @@ static int decode_p_block(FourXContext *f, uint16_t *dst, uint16_t *src, } mcdc(dst, src, log2w, h, stride, 1, bytestream2_get_le16(&f->g2)); } else if (code == 5) { + if (start > src || src > end) { + av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n"); + return AVERROR_INVALIDDATA; + } mcdc(dst, src, log2w, h, stride, 0, bytestream2_get_le16(&f->g2)); } else if (code == 6) { if (log2w) { -- 2.7.4