From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 50A0744F83 for ; Thu, 12 Jan 2023 14:43:27 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id BB1F668B00B; Thu, 12 Jan 2023 16:43:23 +0200 (EET) Received: from relay10.mail.gandi.net (relay10.mail.gandi.net [217.70.178.230]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 42142680039 for ; Thu, 12 Jan 2023 16:43:17 +0200 (EET) Received: (Authenticated sender: michael@niedermayer.cc) by mail.gandi.net (Postfix) with ESMTPSA id 6733A24000D for ; Thu, 12 Jan 2023 14:43:16 +0000 (UTC) Date: Thu, 12 Jan 2023 15:43:15 +0100 From: Michael Niedermayer To: FFmpeg development discussions and patches Message-ID: <20230112144315.GK1949656@pb2> References: <20230111204221.22550-1-michael@niedermayer.cc> MIME-Version: 1.0 In-Reply-To: Subject: Re: [FFmpeg-devel] [PATCH 1/6] avcodec/utils: allocate a line more for VC1 and WMV3 X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 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 Content-Type: multipart/mixed; boundary="===============6017316866239093922==" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: --===============6017316866239093922== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="QxIEt88oQPsT6QmF" Content-Disposition: inline --QxIEt88oQPsT6QmF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 12, 2023 at 08:38:08AM +0100, Andreas Rheinhardt wrote: > Michael Niedermayer: > > Fixes: out of array read on 32bit > > Fixes: 54857/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1_fuzz= er-5840588224462848 > >=20 > > The chroma MC code reads over the currently allocated frame. > > Alternative fixes would be allocating a few bytes more at the end inste= ad of a whole > > line extra or to adjust the threshold where the edge emu code is activa= ted > >=20 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz= /tree/master/projects/ffmpeg > > Signed-off-by: Michael Niedermayer > > --- > > libavcodec/utils.c | 1 + > > 1 file changed, 1 insertion(+) > >=20 > > diff --git a/libavcodec/utils.c b/libavcodec/utils.c > > index 2b63a498b9..1aa0a05a31 100644 > > --- a/libavcodec/utils.c > > +++ b/libavcodec/utils.c > > @@ -321,6 +321,7 @@ void avcodec_align_dimensions2(AVCodecContext *s, i= nt *width, int *height, > > *width =3D FFALIGN(*width, w_align); > > *height =3D FFALIGN(*height, h_align); > > if (s->codec_id =3D=3D AV_CODEC_ID_H264 || s->lowres || > > + s->codec_id =3D=3D AV_CODEC_ID_VC1 || s->codec_id =3D=3D AV_C= ODEC_ID_WMV3 || > > s->codec_id =3D=3D AV_CODEC_ID_VP5 || s->codec_id =3D=3D AV_C= ODEC_ID_VP6 || > > s->codec_id =3D=3D AV_CODEC_ID_VP6F || s->codec_id =3D=3D AV_C= ODEC_ID_VP6A > > ) { >=20 > Does this only happen on 32bit systems? If so, why? Id have to double check, some of the issues in this set where 32bit specifi= c some not But the x86 codepath has special cases i think for non interpolated cases w= hile the C path which was used in the issue does not. A check could also be added to the C path to not read the next line whan no= t needed the patch is just folllowing what h264 does=20 thx [...] --=20 Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB It is what and why we do it that matters, not just one of them. --QxIEt88oQPsT6QmF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABEIAB0WIQSf8hKLFH72cwut8TNhHseHBAsPqwUCY8AceQAKCRBhHseHBAsP q3nAAJ9DTUzJuLisPavAJBsl5pAXlAMAhgCgmzphaPm8RPv5UHG5ZKaVJ6+lhTA= =wyOW -----END PGP SIGNATURE----- --QxIEt88oQPsT6QmF-- --===============6017316866239093922== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe". --===============6017316866239093922==--