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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id o1sm411141pfd.129.2021.08.18.10.58.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Aug 2021 10:58:41 -0700 (PDT) Date: Wed, 18 Aug 2021 10:58:40 -0700 From: Kees Cook To: Miguel Ojeda Cc: linux-kernel , Miguel Ojeda , Nathan Chancellor , Nick Desaulniers , clang-built-linux , Andrew Morton , Daniel Micay , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Vlastimil Babka , Dennis Zhou , Tejun Heo , Masahiro Yamada , Michal Marek , Linux-MM , Linux Kbuild mailing list , linux-hardening@vger.kernel.org Subject: Re: [PATCH 1/5] Compiler Attributes: Add __alloc_size() for better bounds checking Message-ID: <202108181058.2BE1508@keescook> References: <20210818050841.2226600-1-keescook@chromium.org> <20210818050841.2226600-2-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b="EE/CeXz6"; dmarc=pass (policy=none) header.from=chromium.org; spf=pass (imf26.hostedemail.com: domain of keescook@chromium.org designates 209.85.214.179 as permitted sender) smtp.mailfrom=keescook@chromium.org X-Stat-Signature: 7388kq74gazt93jtwx71333ou1amibdr X-Rspamd-Queue-Id: 75882200FCB6 X-Rspamd-Server: rspam05 X-HE-Tag: 1629309523-999439 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Aug 18, 2021 at 03:07:48PM +0200, Miguel Ojeda wrote: > On Wed, Aug 18, 2021 at 7:08 AM Kees Cook wrote: > > > > Clang can additionally use alloc_size to informt the results of > > Typo. > > > Additionally disables -Wno-alloc-size-larger-than since the allocators > > Disables -Walloc-size-larger-than? > > > already reject SIZE_MAX, and the compile-time warnings aren't helpful. > > Perhaps a bit more context here (and/or in the comment in the > Makefile) would be nice: i.e. why are they not helpful (even if > rejected by the allocators). Thanks for the review! I'll get this all fixed for v2. -- Kees Cook