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[112.120.42.27]) by smtp.gmail.com with ESMTPSA id 123sm2680229pgd.83.2020.09.25.08.35.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 25 Sep 2020 08:35:16 -0700 (PDT) Date: Fri, 25 Sep 2020 11:35:09 -0400 From: Peilin Ye To: Daniel Vetter Cc: Jiri Slaby , Greg Kroah-Hartman , Bartlomiej Zolnierkiewicz , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org, syzkaller-bugs@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/3] Prevent out-of-bounds access for built-in font data buffers Message-ID: <20200925153509.GA895804@PWN> References: <0000000000006b9e8d059952095e@google.com> <3f754d60-1d35-899c-4418-147d922e29af@kernel.org> <20200925101300.GA890211@PWN> <20200925132551.GF438822@phenom.ffwll.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200925132551.GF438822@phenom.ffwll.local> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 25, 2020 at 03:25:51PM +0200, Daniel Vetter wrote: > I think the only way to make this work is that we have one place which > takes in the userspace uapi struct, and then converts it once into a > kernel_console_font. With all the error checking. Ah, I didn't think of that! When trying to introduce `kernel_console_font` I ended up using the uapi version and the kernel version in parallel... > Then all internal code deals in terms of kernel_console_font, with > properly typed and named struct members and helper functions and > everything. And we might need a gradual conversion for this, so that first > we can convert over invidual console drivers, then subsystems, until at > the end we've pushed the conversion from uapi array to kernel_console_font > all the way to the ioctl entry points. > > But that's indeed a huge pile of work, and fair warning: fbcon is > semi-orphaned, so by doing this you'll pretty much volunteer for > maintainership :-) > > But I'd be very happy to help get this done and throw some maintainership > credentials at you in the proces ... Sounds exciting, I will be glad to do this! I'm just a beginner, but I will try to do what I can do. Thank you, Peilin Ye