From a68a6a4fb19caecc91d5f7fe3ef4f83f6d3c4586 Mon Sep 17 00:00:00 2001 From: Laurent Aimar Date: Sat, 8 Oct 2011 23:40:34 +0200 Subject: [PATCH] xxan: check for out of bound accesses Signed-off-by: Michael Niedermayer --- libavcodec/xxan.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/libavcodec/xxan.c b/libavcodec/xxan.c index e96e1ddbfe..938a5581c4 100644 --- a/libavcodec/xxan.c +++ b/libavcodec/xxan.c @@ -129,7 +129,9 @@ static int xan_unpack(uint8_t *dest, const int dest_len, if (size + size2 > dest_end - dest) break; } - if (src + size > src_end || dest + size + size2 > dest_end) + if (src + size > src_end || + dest + size + size2 > dest_end || + dest + size - orig_dest < back ) return -1; bytestream_get_buffer(&src, dest, size); dest += size; @@ -194,6 +196,8 @@ static int xan_decode_chroma(AVCodecContext *avctx, AVPacket *avpkt) if (mode) { for (j = 0; j < avctx->height >> 1; j++) { for (i = 0; i < avctx->width >> 1; i++) { + if (src_end - src < 1) + return 0; val = *src++; if (val) { val = AV_RL16(table + (val << 1)); @@ -202,8 +206,6 @@ static int xan_decode_chroma(AVCodecContext *avctx, AVPacket *avpkt) U[i] = uval | (uval >> 5); V[i] = vval | (vval >> 5); } - if (src == src_end) - return 0; } U += s->pic.linesize[1]; V += s->pic.linesize[2]; @@ -214,6 +216,8 @@ static int xan_decode_chroma(AVCodecContext *avctx, AVPacket *avpkt) for (j = 0; j < avctx->height >> 2; j++) { for (i = 0; i < avctx->width >> 1; i += 2) { + if (src_end - src < 1) + return 0; val = *src++; if (val) { val = AV_RL16(table + (val << 1)); @@ -302,6 +306,9 @@ static int xan_decode_frame_type0(AVCodecContext *avctx, AVPacket *avpkt) corr_end - corr_off); if (dec_size < 0) dec_size = 0; + else + dec_size = FFMIN(dec_size, s->buffer_size/2 - 1); + for (i = 0; i < dec_size; i++) s->y_buffer[i*2+1] = (s->y_buffer[i*2+1] + (s->scratch_buffer[i] << 1)) & 0x3F; }