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R . Silva" , Bill Wendling , Justin Stitt , Jann Horn , Przemek Kitszel , Marco Elver , Linus Torvalds , Greg Kroah-Hartman , Sasha Levin , linux-mm@kvack.org, Miguel Ojeda , Nathan Chancellor , Peter Zijlstra , Nick Desaulniers , Jonathan Corbet , Jakub Kicinski , Yafang Shao , Tony Ambardar , Alexander Lobakin , Jan Hendrik Farr , Alexander Potapenko , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-doc@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH v4 2/2] slab: Introduce kmalloc_obj() and family In-Reply-To: <202510071001.11497F6708@keescook> Message-ID: References: <20250315025852.it.568-kees@kernel.org> <20250315031550.473587-2-kees@kernel.org> <202510071001.11497F6708@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 1467110000C X-Stat-Signature: a5hqar1fkyn6jspe5bdxepfmwehyuhyq X-Rspam-User: X-HE-Tag: 1759859242-697116 X-HE-Meta: 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 rROHDUgO QRJuxZHD07l7f849uF/bIfNAZGFQgJq7g3btOPDolrDVtxuyuRP4qZQ4DOF9f7+AzGHp3ijDkjSFIVpsFr5t8vtHfecoeUsKDPuuJtXqesyLaNgum+o2aZ2992Xq/Mfm8vwfM1rdDlotEjRoL75V+dVbQBjcii3QE9rOuybkNnIkJwM/tsOYsiewX3a7+SXpg6BUPVzHxcuYnliTQSjiRsG6M+9WFDf9akMhMDCaYJhs38y2A1JmprFY8CfFScilnuWBEBTxUn6u4G0cLhbApBHFZgPJjORCOxeiDpV5YAmvOLDwJe5REe+cOu07ex+p/VStGBK/ww7rwocfGcQ6UHot/Jbjxr3q7E2VqVChu2qq7Z0gzUvDfGmzmMB6ZEu+cFBu3mDEwebAGxh0GaBK1YJgmB1nu9xHM5zOQ 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: List-Subscribe: List-Unsubscribe: On Tue, 7 Oct 2025, Kees Cook wrote: > But all of that is orthogonal to just _having_ the type info available. iOS did go the path of creating basically one slab cache for each "type" of kmalloc for security reasons. See https://security.apple.com/blog/towards-the-next-generation-of-xnu-memory-safety/