From 4d77a4a54d2f5c34a9cc7d3b3424d16e24515a0f Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 3 Jul 2018 20:33:04 +0200 Subject: [PATCH] avformat/mms: Add missing chunksize check Fixes: out of array read Fixes: mms-crash-01b6c5d85f9d9f40f4e879896103e9f5b222816a Found-by: Paul Ch 1st hunk by Paul Ch Tested-by: Paul Ch Signed-off-by: Michael Niedermayer (cherry picked from commit cced03dd667a5df6df8fd40d8de0bff477ee02e8) Signed-off-by: Michael Niedermayer --- libavformat/mms.c | 44 ++++++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 18 deletions(-) diff --git a/libavformat/mms.c b/libavformat/mms.c index 17fa76a8d4..768fda6525 100644 --- a/libavformat/mms.c +++ b/libavformat/mms.c @@ -94,24 +94,26 @@ int ff_mms_asf_header_parser(MMSContext *mms) } } } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) { - flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24); - stream_id = flags & 0x7F; - //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size, - //we can calculate the packet size by stream_num. - //Please see function send_stream_selection_request(). - if (mms->stream_num < MMS_MAX_STREAMS && - 46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) { - mms->streams = av_fast_realloc(mms->streams, - &mms->nb_streams_allocated, - (mms->stream_num + 1) * sizeof(MMSStream)); - if (!mms->streams) - return AVERROR(ENOMEM); - mms->streams[mms->stream_num].id = stream_id; - mms->stream_num++; - } else { - av_log(NULL, AV_LOG_ERROR, - "Corrupt stream (too many A/V streams)\n"); - return AVERROR_INVALIDDATA; + if (end - p >= (sizeof(ff_asf_guid) * 3 + 26)) { + flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24); + stream_id = flags & 0x7F; + //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size, + //we can calculate the packet size by stream_num. + //Please see function send_stream_selection_request(). + if (mms->stream_num < MMS_MAX_STREAMS && + 46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) { + mms->streams = av_fast_realloc(mms->streams, + &mms->nb_streams_allocated, + (mms->stream_num + 1) * sizeof(MMSStream)); + if (!mms->streams) + return AVERROR(ENOMEM); + mms->streams[mms->stream_num].id = stream_id; + mms->stream_num++; + } else { + av_log(NULL, AV_LOG_ERROR, + "Corrupt stream (too many A/V streams)\n"); + return AVERROR_INVALIDDATA; + } } } else if (!memcmp(p, ff_asf_ext_stream_header, sizeof(ff_asf_guid))) { if (end - p >= 88) { @@ -143,6 +145,12 @@ int ff_mms_asf_header_parser(MMSContext *mms) } } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) { chunksize = 46; // see references [2] section 3.4. This should be set 46. + if (chunksize > end - p) { + av_log(NULL, AV_LOG_ERROR, + "Corrupt stream (header chunksize %"PRId64" is invalid)\n", + chunksize); + return AVERROR_INVALIDDATA; + } } p += chunksize; }