From 2a0fb7286d67c47e44aa76c237ede117b22af616 Mon Sep 17 00:00:00 2001 From: Reinhard Tartler Date: Sun, 8 Dec 2013 13:24:26 -0500 Subject: [PATCH] alsdec: check block length Fix writing over the end Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind Addresses: CVE-2013-0845 --- libavcodec/alsdec.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c index 782a1b8b80..f7dee7de12 100644 --- a/libavcodec/alsdec.c +++ b/libavcodec/alsdec.c @@ -1376,6 +1376,11 @@ static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame) for (b = 0; b < ctx->num_blocks; b++) { bd.block_length = div_blocks[b]; + if (bd.block_length <= 0) { + av_log(ctx->avctx, AV_LOG_WARNING, + "Invalid block length %d in channel data!\n", bd.block_length); + continue; + } for (c = 0; c < avctx->channels; c++) { bd.const_block = ctx->const_block + c;