From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FDBEC433B4 for ; Thu, 22 Apr 2021 06:57:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DAD661459 for ; Thu, 22 Apr 2021 06:57:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234999AbhDVG62 (ORCPT ); Thu, 22 Apr 2021 02:58:28 -0400 Received: from mail-vs1-f44.google.com ([209.85.217.44]:44651 "EHLO mail-vs1-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234976AbhDVG61 (ORCPT ); Thu, 22 Apr 2021 02:58:27 -0400 Received: by mail-vs1-f44.google.com with SMTP id t23so6044720vso.11; Wed, 21 Apr 2021 23:57:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4foBw09MDw6s3pXeHYY2a07YfZSi/nyyHNfjUeyH1VU=; b=M8WUUI0HfZlLeryijBdLqI5EICYOkWqHO5NYuv/GubYr5K8grBMpadIo7XHxhSp/9h ExYxHtK4C09Zjki/MkeqnIQTOec8GQx7RP7trgxfsQe50H2IqGV2dz83JAcXnuRDg8fJ OMtN/2tCHz+dT610357pf/kRfatWkVlzYRPn3aUn8Vtp4GvgL9fkEG0hdXYVIaqJStuY zEJA+HPajlEq8CLyuJ3h0opeKg1yuTtD0B2T1aEWdrr4GdtflstF7Kmj1K3RC9GEihl1 s2rIkHN41nRz9DV5a7hb++YMMJEqiplunA8dg/9f5gxHVUm4VUHA7g9P9WyafDeYOzb1 Ufpw== X-Gm-Message-State: AOAM532iGnozgwqSk4yPsggNDWilhv5z7siTNJFJP/JgW5/DSjzmOpv4 7EkFOJgAnbtI0aJ76oN2R1IeRNjK2BkZvYljl/w= X-Google-Smtp-Source: ABdhPJyOjs5ar2yehQ6u0OsOpuk5qctA0sHyTLkAEf/YwE4Ttu+Zj/JaO+TzLjr4hTLSCU9NA0rCHT7xEOAQunIXbuc= X-Received: by 2002:a67:fc57:: with SMTP id p23mr1176649vsq.40.1619074672248; Wed, 21 Apr 2021 23:57:52 -0700 (PDT) MIME-Version: 1.0 References: <20210421130105.1226686-1-gregkh@linuxfoundation.org> <20210421130105.1226686-74-gregkh@linuxfoundation.org> In-Reply-To: From: Geert Uytterhoeven Date: Thu, 22 Apr 2021 08:57:41 +0200 Message-ID: Subject: Re: [PATCH 073/190] Revert "media: rcar_drif: fix a memory disclosure" To: Laurent Pinchart Cc: Greg Kroah-Hartman , Linux Kernel Mailing List , Kangjie Lu , Hans Verkuil , Mauro Carvalho Chehab , Fabrizio Castro , Linux-Renesas , =?UTF-8?Q?Niklas_S=C3=B6derlund?= Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Laurent, On Wed, Apr 21, 2021 at 11:22 PM Laurent Pinchart wrote: > On Wed, Apr 21, 2021 at 08:58:22PM +0200, Geert Uytterhoeven wrote: > > On Wed, Apr 21, 2021 at 3:06 PM Greg Kroah-Hartman wrote: > > > This reverts commit d39083234c60519724c6ed59509a2129fd2aed41. > > > > > > Commits from @umn.edu addresses have been found to be submitted in "bad > > > faith" to try to test the kernel community's ability to review "known > > > malicious" changes. The result of these submissions can be found in a > > > paper published at the 42nd IEEE Symposium on Security and Privacy > > > entitled, "Open Source Insecurity: Stealthily Introducing > > > Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University > > > of Minnesota) and Kangjie Lu (University of Minnesota). > > > > > > Because of this, all submissions from this group must be reverted from > > > the kernel tree and will need to be re-reviewed again to determine if > > > they actually are a valid fix. Until that work is complete, remove this > > > change to ensure that no problems are being introduced into the > > > codebase. > > > > > > Cc: Kangjie Lu > > > Cc: Geert Uytterhoeven > > > Cc: Hans Verkuil > > > Cc: Mauro Carvalho Chehab > > > Signed-off-by: Greg Kroah-Hartman > > > > Upon a second look, I still see nothing wrong with the original commit. > > However, as I'm no v4l expert, I'd like to defer to the experts for final > > judgement. > > It seems fine to me, but it also seems unneeded, as the V4L2 core clears > the whole f->fmt union before calling this operation. The revert will > this improve performance very slightly. Hmm, that means very recent commit f12b81e47f48940a ("media: core headers: fix kernel-doc warnings") is not fully correct, as it added kerneldoc stating this is the responsibility of the driver: + * @reserved: drivers and applications must zero this array Anyway, it doesn't look like this umn.edu patch introduced a bug. > > > --- a/drivers/media/platform/rcar_drif.c > > > +++ b/drivers/media/platform/rcar_drif.c > > > @@ -915,7 +915,6 @@ static int rcar_drif_g_fmt_sdr_cap(struct file *file, void *priv, > > > { > > > struct rcar_drif_sdr *sdr = video_drvdata(file); > > > > > > - memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved)); > > > f->fmt.sdr.pixelformat = sdr->fmt->pixelformat; > > > f->fmt.sdr.buffersize = sdr->fmt->buffersize; Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds