From patchwork Thu Sep 22 03:10:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 12984457 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75964C32771 for ; Thu, 22 Sep 2022 03:14:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231229AbiIVDOF (ORCPT ); Wed, 21 Sep 2022 23:14:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231310AbiIVDL7 (ORCPT ); Wed, 21 Sep 2022 23:11:59 -0400 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3162999B7E for ; Wed, 21 Sep 2022 20:10:32 -0700 (PDT) Received: by mail-pl1-x62f.google.com with SMTP id d24so7546384pls.4 for ; Wed, 21 Sep 2022 20:10:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=bpEbyFBm8ujPK6iqrGWXCPwqEismRLAX26z3I+Rspz8=; b=GwEKRlSGWNZZz0bSOhH09wT/dIlAzUgEDzlKCcSGfqUiFWltnmUuICqFqj3LlzCRek BVgZYAczODxRtxBqW9kNHbHyqaba8VuQcAtk82kUBEiaAlU+daUZZIQGOA7CX1koggEg yep8B8ilhj99/u+e0tErmzGRiobAHfyNKzCog= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date; bh=bpEbyFBm8ujPK6iqrGWXCPwqEismRLAX26z3I+Rspz8=; b=c1fxy4EBVXa+dnn8pDk9rPD+oZxYA5zu9yLR1n+Xnwu82dSkfb8PCbKLXy1CP7HGb5 PmHG/jueUDfguMrZx7H8GfpwvPmgD8nNWjnkvGC4qsw0zfhIuSC/wvJdJ+p1Ht0bwmao pfDLmxvwl6Kf9NNGWu3XQacIUycR+6tT/Hj44d4g4d+7KZJALeNyVR181tBTgTv23vC4 cw6StGY/xt8r8CLP+IxaEgGIzgj1RecfLn0tCjLC5oWOWbOukf2R3fl3/Gu42Li9siDm K1GS7Dbn3gKAYo3zPpwrFJ5Ql3RuuUUy4/LSJlHrL+eyAz0Voc8iNR3nOY6gcIMYxSjl IA/w== X-Gm-Message-State: ACrzQf13Z1+fU2TXLGxa/u1hb9WtHxKNe67EzVxGueFmAN3X4JAE+LZF 2ju+Kn4qDmUL97OqD5iGbeqlMQ== X-Google-Smtp-Source: AMsMyM5u6eYb4g944r9Q/Pt9mZXCmsyxQzDwy9CZJ8oZsRhkZQrJS6fEKVkXWUHzQQ89FNa93/Kc0w== X-Received: by 2002:a17:902:e54b:b0:177:e29e:a0c0 with SMTP id n11-20020a170902e54b00b00177e29ea0c0mr1359878plf.66.1663816231700; Wed, 21 Sep 2022 20:10:31 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id u3-20020a17090341c300b0016d6963cb12sm2781495ple.304.2022.09.21.20.10.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Sep 2022 20:10:26 -0700 (PDT) From: Kees Cook To: Vlastimil Babka Cc: Kees Cook , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Nick Desaulniers , Hao Luo , Marco Elver , linux-mm@kvack.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Greg Kroah-Hartman , Alex Elder , Josef Bacik , David Sterba , Sumit Semwal , =?utf-8?q?Christian_K=C3=B6nig?= , Jesse Brandeburg , Daniel Micay , Yonghong Song , Miguel Ojeda , Jacob Shin , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-fsdevel@vger.kernel.org, intel-wired-lan@lists.osuosl.org, dev@openvswitch.org, x86@kernel.org, linux-wireless@vger.kernel.org, llvm@lists.linux.dev, linux-hardening@vger.kernel.org Subject: [PATCH 11/12] slab: Remove __malloc attribute from realloc functions Date: Wed, 21 Sep 2022 20:10:12 -0700 Message-Id: <20220922031013.2150682-12-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220922031013.2150682-1-keescook@chromium.org> References: <20220922031013.2150682-1-keescook@chromium.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3544; h=from:subject; bh=oS2Iv+uVGC72Kt/ZsRdKSQv1v3zTVhJ3IWvWWRabp+g=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBjK9IUEKv90igkAnqqd37b6kR1bxxEz6G+6mdwmL8d hU8qttyJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYyvSFAAKCRCJcvTf3G3AJqdIEA CK12iuKhH2Gb+F4wapUYpaSc373MS6rjJoFpsNm84+/ObvNHGEz2kq5kYHkOs7G3e8jhHlr4YXru45 YnbkR3SRCmUyJ7loADAzHlj0yCxkYniAAXvuZzfvc9luBT3TIsBLzOyoo8E8ylHkAK0aVycGXvAy+W PGkSD/jL+EQrHdUK+hra5t32/YXsbXr4NStVZ9IzHolQ9EI054AF8/LV77MBWpPIX5Ho1mGWzl1ijJ E9wFPHhl2hfKzU9eXD+N4EzOrlLceF+ztZPDuq2MdUfMxOdv5GAJKiW5FRq+IFpNkwIM9nhSPM5iQE YBr/ivEWQqdNFsPnRtgWssO370vtzYb+x61dFRrUn7/FKR7Om27TEYwAd6+P+FnDwRoMTV/BPuFe6C 7iiHIRbFsfrIUn/r4jYTZt4u6NtpaDA1FVV/Em1JDkKtSh3fWi4Ku18TGZQm81iMdScRZHubomFfI+ vxHjePLahrOHkSfaNZvuJLrLPDU7WsDADYD6e/53VTiL3yyHRtO0XH1DyMkIDUA2WPNZy6ISq70TQ5 eN54uMg3p8o5Bz9r112LSXwEkIA+2aRlSgWZDi0KwDLacLHhcuECUcvzHrANynElUzrtH5uoqtYyZh Y8ppyJSFYyPmpNrkQ/M6ZKVaeCwZCHu2ZcgtL5o8/NTiuMaB6SQl9nFcWJRg== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The __malloc attribute should not be applied to "realloc" functions, as the returned pointer may alias the storage of the prior pointer. Instead of splitting __malloc from __alloc_size, which would be a huge amount of churn, just create __realloc_size for the few cases where it is needed. Additionally removes the conditional test for __alloc_size__, which is always defined now. Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: Nick Desaulniers Cc: Hao Luo Cc: Marco Elver Cc: linux-mm@kvack.org Signed-off-by: Kees Cook --- include/linux/compiler_types.h | 13 +++++-------- include/linux/slab.h | 12 ++++++------ 2 files changed, 11 insertions(+), 14 deletions(-) diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 4f2a819fd60a..f141a6f6b9f6 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -271,15 +271,12 @@ struct ftrace_likely_data { /* * Any place that could be marked with the "alloc_size" attribute is also - * a place to be marked with the "malloc" attribute. Do this as part of the - * __alloc_size macro to avoid redundant attributes and to avoid missing a - * __malloc marking. + * a place to be marked with the "malloc" attribute, except those that may + * be performing a _reallocation_, as that may alias the existing pointer. + * For these, use __realloc_size(). */ -#ifdef __alloc_size__ -# define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc -#else -# define __alloc_size(x, ...) __malloc -#endif +#define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc +#define __realloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) #ifndef asm_volatile_goto #define asm_volatile_goto(x...) asm goto(x) diff --git a/include/linux/slab.h b/include/linux/slab.h index 4fc41e4ed4a2..ac3832b50dbb 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -184,7 +184,7 @@ int kmem_cache_shrink(struct kmem_cache *s); /* * Common kmalloc functions provided by all allocators */ -void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __alloc_size(2); +void * __must_check krealloc(const void *objp, size_t new_size, gfp_t flags) __realloc_size(2); void kfree(const void *objp); void kfree_sensitive(const void *objp); size_t __ksize(const void *objp); @@ -661,10 +661,10 @@ static inline __alloc_size(1, 2) void *kmalloc_array(size_t n, size_t size, gfp_ * @new_size: new size of a single member of the array * @flags: the type of memory to allocate (see kmalloc) */ -static inline __alloc_size(2, 3) void * __must_check krealloc_array(void *p, - size_t new_n, - size_t new_size, - gfp_t flags) +static inline __realloc_size(2, 3) void * __must_check krealloc_array(void *p, + size_t new_n, + size_t new_size, + gfp_t flags) { size_t bytes; @@ -788,7 +788,7 @@ static inline __alloc_size(1, 2) void *kvcalloc(size_t n, size_t size, gfp_t fla } extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags) - __alloc_size(3); + __realloc_size(3); extern void kvfree(const void *addr); extern void kvfree_sensitive(const void *addr, size_t len);