From patchwork Thu Mar 2 02:02:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Niedermayer X-Patchwork-Id: 2722 Delivered-To: ffmpegpatchwork@gmail.com Received: by 10.103.31.14 with SMTP id f14csp39782vsf; Wed, 1 Mar 2017 18:03:01 -0800 (PST) X-Received: by 10.28.175.138 with SMTP id y132mr6066841wme.86.1488420181160; Wed, 01 Mar 2017 18:03:01 -0800 (PST) Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org. [79.124.17.100]) by mx.google.com with ESMTP id 64si8818070wrn.92.2017.03.01.18.03.00; Wed, 01 Mar 2017 18:03:01 -0800 (PST) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 861D168829D; Thu, 2 Mar 2017 04:02:39 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from vie01a-dmta-pe02-3.mx.upcmail.net (vie01a-dmta-pe02-3.mx.upcmail.net [62.179.121.159]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id AACCF688287 for ; Thu, 2 Mar 2017 04:02:33 +0200 (EET) Received: from [172.31.216.43] (helo=vie01a-pemc-psmtp-pe01) by vie01a-dmta-pe02.mx.upcmail.net with esmtp (Exim 4.87) (envelope-from ) id 1cjG4q-0008H1-1r for ffmpeg-devel@ffmpeg.org; Thu, 02 Mar 2017 03:02:44 +0100 Received: from localhost ([213.47.41.20]) by vie01a-pemc-psmtp-pe01 with SMTP @ mailcloud.upcmail.net id qq291u0110S5wYM01q2Awo; Thu, 02 Mar 2017 03:02:10 +0100 X-SourceIP: 213.47.41.20 From: Michael Niedermayer To: FFmpeg development discussions and patches Date: Thu, 2 Mar 2017 03:02:07 +0100 Message-Id: <20170302020207.23854-2-michael@niedermayer.cc> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170302020207.23854-1-michael@niedermayer.cc> References: <20170302020207.23854-1-michael@niedermayer.cc> Subject: [FFmpeg-devel] [PATCH 2/2] avcodec/mpeg4videodec: Improve the overflow checks in mpeg4_decode_sprite_trajectory() 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 MIME-Version: 1.0 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Also clear the state on errors Fixes integer overflows in 701/clusterfuzz-testcase-6594719951880192 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mpeg4videodec.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c index 9f9374d550..568263ecdf 100644 --- a/libavcodec/mpeg4videodec.c +++ b/libavcodec/mpeg4videodec.c @@ -375,7 +375,7 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g FFABS(s->sprite_offset[1][1]) >= INT_MAX >> shift_c ) { avpriv_request_sample(s->avctx, "Too large sprite shift or offset"); - return AVERROR_PATCHWELCOME; + goto overflow; } for (i = 0; i < 2; i++) { @@ -385,17 +385,23 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g s->sprite_delta[1][i] *= 1 << shift_y; ctx->sprite_shift[i] = 16; - if (llabs(s->sprite_offset[i][0] + s->sprite_delta[i][0] * (int64_t)w) >= INT_MAX || - llabs(s->sprite_offset[i][0] + s->sprite_delta[i][1] * (int64_t)h) >= INT_MAX || - llabs(s->sprite_offset[i][0] + s->sprite_delta[i][0] * (int64_t)w + s->sprite_delta[i][1] * (int64_t)h) >= INT_MAX) { + } + for (i = 0; i < 2; i++) { + if (llabs(s->sprite_offset[0][i] + s->sprite_delta[i][0] * (w+16LL)) >= INT_MAX || + llabs(s->sprite_offset[0][i] + s->sprite_delta[i][1] * (h+16LL)) >= INT_MAX || + llabs(s->sprite_offset[0][i] + s->sprite_delta[i][0] * (w+16LL) + s->sprite_delta[i][1] * (h+16LL)) >= INT_MAX) { avpriv_request_sample(s->avctx, "Overflow on sprite points"); - return AVERROR_PATCHWELCOME; + goto overflow; } } s->real_sprite_warping_points = ctx->num_sprite_warping_points; } return 0; +overflow: + memset(s->sprite_offset, 0, sizeof(s->sprite_offset)); + memset(s->sprite_delta, 0, sizeof(s->sprite_delta)); + return AVERROR_PATCHWELCOME; } static int decode_new_pred(Mpeg4DecContext *ctx, GetBitContext *gb) {