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R. Silva" , iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] iommu/vt-d: Use kcalloc() instead of kzalloc() Message-ID: <202402121031.4649560C1@keescook> References: <20240211175143.9229-1-erick.archer@gmx.com> 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: <20240211175143.9229-1-erick.archer@gmx.com> On Sun, Feb 11, 2024 at 06:51:43PM +0100, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > Here the multiplication is obviously safe because DMAR_LATENCY_NUM > is the number of latency types defined in the "latency_type" enum. > > enum latency_type { > DMAR_LATENCY_INV_IOTLB = 0, > DMAR_LATENCY_INV_DEVTLB, > DMAR_LATENCY_INV_IEC, > DMAR_LATENCY_PRQ, > DMAR_LATENCY_NUM > }; > > However, using kcalloc() is more appropriate [2] and improves > readability. This patch has no effect on runtime behavior. > > Link: https://github.com/KSPP/linux/issues/162 [1] > Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] > Signed-off-by: Erick Archer Looks reasonable. Reviewed-by: Kees Cook -- Kees Cook