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R. Silva" , Justin Stitt , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] perf/ring_buffer: Prefer struct_size over open coded arithmetic Message-ID: <202405011317.AF41B94B@keescook> References: <20240430091504.GC40213@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240430091504.GC40213@noisy.programming.kicks-ass.net> On Tue, Apr 30, 2024 at 11:15:04AM +0200, Peter Zijlstra wrote: > On Mon, Apr 29, 2024 at 07:40:58PM +0200, Erick Archer wrote: > > This is an effort to get rid of all multiplications from allocation > > functions in order to prevent integer overflows [1][2]. > > So personally I detest struct_size() because I can never remember wtf it > does, whereas the code it replaces is simple and straight forward :/ Sure, new APIs can involved a learning curve. If we can all handle container_of(), we can deal with struct_size(). :) -- Kees Cook