From patchwork Fri Nov 15 23:10:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 16291 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id 52BA544A324 for ; Sat, 16 Nov 2019 01:13:35 +0200 (EET) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 44BB868A633; Sat, 16 Nov 2019 01:13:35 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe06-1.mx.upcmail.net (vie01a-dmta-pe06-1.mx.upcmail.net [84.116.36.14]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id E718C68A31D for ; Sat, 16 Nov 2019 01:13:26 +0200 (EET) Received: from [172.31.216.235] (helo=vie01a-pemc-psmtp-pe12.mail.upcmail.net) by vie01a-dmta-pe06.mx.upcmail.net with esmtp (Exim 4.92) (envelope-from ) id 1iVkmL-0003FV-0C for ffmpeg-devel@ffmpeg.org; Sat, 16 Nov 2019 00:13:25 +0100 Received: from localhost ([213.47.68.29]) by vie01a-pemc-psmtp-pe12.mail.upcmail.net with ESMTP id VklMiMtsVwlysVklMiKpSf; Sat, 16 Nov 2019 00:12:24 +0100 X-Env-Mailfrom: michael@niedermayer.cc X-Env-Rcptto: ffmpeg-devel@ffmpeg.org X-SourceIP: 213.47.68.29 X-CNFS-Analysis: v=2.3 cv=E5OzWpVl c=1 sm=1 tr=0 a=2hcxjKEKjp0CzLx6oWAm4g==:117 a=2hcxjKEKjp0CzLx6oWAm4g==:17 a=MKtGQD3n3ToA:10 a=1oJP67jkp3AA:10 a=GEAsPZ9sns4A:10 a=ZZnuYtJkoWoA:10 a=nZOtpAppAAAA:20 a=T2hZpfpzAIFY2hnUpKQA:9 a=1fhp2MxaeJtTNGEnv6mo:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=jd6J4Gguk5HxikPWLKER:22 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Sat, 16 Nov 2019 00:10:52 +0100 Message-Id: <20191115231053.2569-1-michael@niedermayer.cc> X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 X-CMAE-Envelope: MS4wfOF9xscNe3rAknp+VQpAOMGn5XA1pkKMnz+NOqNAKVFavtRZjBuu8yVTfYMoGR1umfPckzBHOQjIgzPBG1xbOQDAcGtZC1doMBmPQn3Fl/FX8wX73Ttj 4YiwXgMIqfGK1KV4AAfWMoUFsO7Z3nvA5jKrCid3G0hcI6umBnY4ROIn Subject: [FFmpeg-devel] [PATCH 1/2] avformat/rmdec: Initialize and sanity check offset in ivr_read_header() X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Fixes: signed integer overflow: -9223372036854775808 - 17 cannot be represented in type 'long' Fixes: 18768/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5674385247830016 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavformat/rmdec.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/libavformat/rmdec.c b/libavformat/rmdec.c index e612c42e57..a951ac8b4d 100644 --- a/libavformat/rmdec.c +++ b/libavformat/rmdec.c @@ -1174,7 +1174,7 @@ static int ivr_read_header(AVFormatContext *s) uint8_t key[256], val[256]; AVIOContext *pb = s->pb; AVStream *st; - int64_t pos, offset, temp; + int64_t pos, offset=0, temp; pos = avio_tell(pb); tag = avio_rl32(pb); @@ -1191,6 +1191,8 @@ static int ivr_read_header(AVFormatContext *s) offset = temp; temp = avio_rb64(pb); } + if (offset <= 0) + return AVERROR_INVALIDDATA; avio_skip(pb, offset - avio_tell(pb)); if (avio_r8(pb) != 1) return AVERROR_INVALIDDATA;