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 AD23544AB6 for ; Wed, 2 Nov 2022 21:31:38 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id D58DC68BEB7; Wed, 2 Nov 2022 23:31:35 +0200 (EET) Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 7C73A68BEB7 for ; Wed, 2 Nov 2022 23:31:29 +0200 (EET) Received: (Authenticated sender: michael@niedermayer.cc) by mail.gandi.net (Postfix) with ESMTPSA id C17A4C0008 for ; Wed, 2 Nov 2022 21:31:28 +0000 (UTC) Date: Wed, 2 Nov 2022 22:31:27 +0100 From: Michael Niedermayer To: FFmpeg development discussions and patches Message-ID: <20221102213127.GJ1814017@pb2> References: <20221102210239.1689-1-michael@niedermayer.cc> <20221102210239.1689-2-michael@niedermayer.cc> <20221102210714.GI1814017@pb2> MIME-Version: 1.0 In-Reply-To: Subject: Re: [FFmpeg-devel] [PATCH 2/2] swscale/output: Bias 16bps output calculations to improve non overflowing range for GBRP16/GBRPF32 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="===============2080737892743980402==" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: --===============2080737892743980402== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="Do4IU1xF/9sod/r6" Content-Disposition: inline --Do4IU1xF/9sod/r6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Nov 02, 2022 at 10:16:57PM +0100, Andreas Rheinhardt wrote: > Michael Niedermayer: > > On Wed, Nov 02, 2022 at 10:02:39PM +0100, Michael Niedermayer wrote: > >> Fixes: integer overflow > >> Signed-off-by: Michael Niedermayer > >> --- > >> libswscale/output.c | 25 +++++++++++-------------- > >> libswscale/x86/output.asm | 16 +++++++++++++++- > >> 2 files changed, 26 insertions(+), 15 deletions(-) > >=20 > > Note, these corner case overflows could affect some of the similary > > implemented cases that are not depth 16 too > >=20 > > ill fix them if issues are replicated > >=20 >=20 > The checkasm-sw_gbrp runs into many overflows (when run under UBSan); > e.g. fate.ffmpeg.org tells me of an issue in line 2289. Said line is not > touched in your commits. checkasm-sw_gbrp feeds random data widely outside sane ranges in. the test certainly makes no sense for testing asm. There is no point in matching C for widely invalid cases. Of cousre we shouldnt overflow if any of this can be triggered with valid and real input (which probably can be done in some cases) thx [...] --=20 Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Elect your leaders based on what they did after the last election, not based on what they say before an election. --Do4IU1xF/9sod/r6 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABEIAB0WIQSf8hKLFH72cwut8TNhHseHBAsPqwUCY2LhqAAKCRBhHseHBAsP qxi/AJ9A2VikEyvQUrPCpD/H8HS54Ik1oACfcuzEta+QeMKqbNAsSwjZLirc8Fg= =Js+z -----END PGP SIGNATURE----- --Do4IU1xF/9sod/r6-- --===============2080737892743980402== 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". --===============2080737892743980402==--