From e398990eb87785e20e065cd3f14d1dbb69df4392 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 5 Mar 2013 02:19:12 +0100 Subject: [PATCH] msrledec: fix output_end checks Fixes out of array accesses Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind Signed-off-by: Michael Niedermayer --- libavcodec/msrledec.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/libavcodec/msrledec.c b/libavcodec/msrledec.c index cd0a73decf..83d7d134b1 100644 --- a/libavcodec/msrledec.c +++ b/libavcodec/msrledec.c @@ -138,7 +138,8 @@ static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVPicture *pic, unsigned int width= FFABS(pic->linesize[0]) / (depth >> 3); output = pic->data[0] + (avctx->height - 1) * pic->linesize[0]; - output_end = pic->data[0] + avctx->height * pic->linesize[0]; + output_end = output + FFABS(pic->linesize[0]); + while (bytestream2_get_bytes_left(gb) > 0) { p1 = bytestream2_get_byteu(gb); if(p1 == 0) { //Escape code @@ -155,6 +156,7 @@ static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVPicture *pic, } } output = pic->data[0] + line * pic->linesize[0]; + output_end = output + FFABS(pic->linesize[0]); pos = 0; continue; } else if(p2 == 1) { //End-of-picture @@ -169,11 +171,11 @@ static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVPicture *pic, return -1; } output = pic->data[0] + line * pic->linesize[0] + pos * (depth >> 3); + output_end = pic->data[0] + line * pic->linesize[0] + FFABS(pic->linesize[0]); continue; } // Copy data - if ((pic->linesize[0] > 0 && output + p2 * (depth >> 3) > output_end) || - (pic->linesize[0] < 0 && output + p2 * (depth >> 3) < output_end)) { + if (output + p2 * (depth >> 3) > output_end) { bytestream2_skip(gb, 2 * (depth >> 3)); continue; } else if (bytestream2_get_bytes_left(gb) < p2 * (depth >> 3)) { @@ -203,8 +205,7 @@ static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVPicture *pic, pos += p2; } else { //run of pixels uint8_t pix[3]; //original pixel - if ((pic->linesize[0] > 0 && output + p1 * (depth >> 3) > output_end) || - (pic->linesize[0] < 0 && output + p1 * (depth >> 3) < output_end)) + if (output + p1 * (depth >> 3) > output_end) continue; switch(depth){