From patchwork Fri Nov 18 03:51:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 13047690 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8D75C4332F for ; Fri, 18 Nov 2022 03:52:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id F27C66B0073; Thu, 17 Nov 2022 22:52:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EAF906B0075; Thu, 17 Nov 2022 22:52:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D29718E0001; Thu, 17 Nov 2022 22:52:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id BE9196B0073 for ; Thu, 17 Nov 2022 22:52:03 -0500 (EST) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 8BB6DAA9C0 for ; Fri, 18 Nov 2022 03:52:03 +0000 (UTC) X-FDA: 80145189726.16.AE7107A Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) by imf15.hostedemail.com (Postfix) with ESMTP id 2EB53A0008 for ; Fri, 18 Nov 2022 03:52:02 +0000 (UTC) Received: by mail-pf1-f176.google.com with SMTP id d192so3769004pfd.0 for ; Thu, 17 Nov 2022 19:52:02 -0800 (PST) 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 :message-id:reply-to; bh=Kl2HCmuKXCRtuCV8keQkppjI9HHVusIDw26V+KNW/hE=; b=TvL+I/WOxW0UWgdWvgJ0gvY2Fk0cjOtxylk/v1UA6dttCvpI1kE/XpZJv57lTN1ZSQ 9zfsGIldon1ArmWFGGhT0hzWaukocjI+WLMq+JWyItCq99MGxbLnN/hq2lmyIomVrFrf KpZuajZ/wA7ltdKsh4/x05FY/9udPWBqve9qc= 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:message-id:reply-to; bh=Kl2HCmuKXCRtuCV8keQkppjI9HHVusIDw26V+KNW/hE=; b=oV0uf+5nivhlf4vAN3oOoy+jGOSmMOOeZSdpNg1g1kzvAjYfJ9rnUjau6KNqEBT3KJ 0oc1uG197rWWxK9akQS8I97qEmqK3XxOjbugb+ohnFWfiHoq47esLrGUeH05a9q7vbR/ E+/k8qKBoP3uc5TeNrszrBp14/Dnl2HkeLXrcstEZfckFReThGNwOnJusn1vrCxJLBSN pEoElUiFP2SCDxUim7n/tIRFw2EUO99LkQobWOer/dd4cqoKhKpTnHWEpvBL2bvYPYOY /rp2vx18MrNT+Z2No8YP59I4MktnFD/Zde8mjE6D/Mbo5kyuPc2RTCrInjP5w9bfkVRj 9pig== X-Gm-Message-State: ANoB5pkfhDABAdTa+QmJtP/voIjrCip+qJF433qwRR/HuS+WnjMtfwRv NFjDsjUMNy3yp2LCESRkDihOzQ== X-Google-Smtp-Source: AA0mqf7HS6tS+6S6c48a5+nH45KT6BsUA5aJzuSM7l/pjNwX3dKMq7yLshBvt6nVve0qTN8OxxufbA== X-Received: by 2002:a63:42c5:0:b0:460:9fe9:d325 with SMTP id p188-20020a6342c5000000b004609fe9d325mr4873891pga.608.1668743522250; Thu, 17 Nov 2022 19:52:02 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id d8-20020a170902cec800b00186e2b3e12fsm2254854plg.261.2022.11.17.19.52.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 19:52:01 -0800 (PST) From: Kees Cook To: Vlastimil Babka Cc: Kees Cook , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 1/2] slab: Clean up SLOB vs kmalloc() definition Date: Thu, 17 Nov 2022 19:51:58 -0800 Message-Id: <20221118035200.1269184-1-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221118034713.gonna.754-kees@kernel.org> References: <20221118034713.gonna.754-kees@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2026; h=from:subject; bh=XCqnPjfv4o/NKArWFRHDgYWfDTlT2kWs5IGt+A3wTyQ=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBjdwFfTA7j/LHUkXVUp6HAaWlDXQgvh/IdCZT/aouq MnYGyIOJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCY3cBXwAKCRCJcvTf3G3AJp8VEA CnjcKb2iCpqmX0eLs3YrJn7gR2VmSD2hbc20QVLE5MxIZJBJgcap3GTy5i1qgCFw2KASeJLxX0fboz KIcE1Mw81hfNEkXWK6vKZ5xFg/pYKmvV6RV7AyQC947FQXvZIi0BaGFsNkS1H1zkCCkAeVMfN80mI0 1dX8ervJ42PpR9KAL7ySYtqYc5nKiffXK78XUMp0GBTZPg5qaurwfYUORKYh3QgkS5uq37EH6B5l0T uHDTLHL8dx2eDshTmfH5c+aw49XVD8zMUwoFc1A1jeD4exIqQHuOahoU0ZSyyjQW1LRXIQTuCzVJC/ o+tEaCPzfAVUa/qfEBHzHbRQW7rMwSguwAz0QAb+bdJLKrN7MR/LtheapmaVMGQjpjJU3Z3DPEt/wi Aq0IbtyxN6RooERZkVULRpRfS9DRzUv6YnmAXOhC0nXVnSVkHSGjOHyjnRfRDxizmrGvl2J0ZORyGE ehH2e6SDBf8yXy3C2gujb+9Xemv/Z2BxHV4BzI46EpD2x9xHZdgIoffQYFanYzr3R8BADb8voGurr+ PSgtL/PqvYl1cj6TsrtAgXAMpDc4VyT7rSMYo6rpO9XUYPhy9iH8YvnGWQ/R5/YwaqcOYjZ2Qq5KpN h6BaSq7PorQjdZiIwkoCEbhD9KEgyIBjAavfzOHXAo+MmXKGPmUKxMabAB2w== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1668743523; a=rsa-sha256; cv=none; b=WBm162NNnKvVQhGB67xMEdFLH7WEHq5Kc5nFKvTMgKGxGP6Y4+801soI5mfrT4S9IZHTEh Dw2JrpTYZZlUAz6+VMs6408ZYcGLrn+InK6ZJu4MSUMMMncm81GzVhNjXU8K4hRgBEDAjM fJA/qrUWZYh8CpLvRezfmSzZ3rA9GJA= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b="TvL+I/WO"; spf=pass (imf15.hostedemail.com: domain of keescook@chromium.org designates 209.85.210.176 as permitted sender) smtp.mailfrom=keescook@chromium.org; dmarc=pass (policy=none) header.from=chromium.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668743523; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Kl2HCmuKXCRtuCV8keQkppjI9HHVusIDw26V+KNW/hE=; b=Agb5njkWxMwh/uZ3xDbr6z0NKRNE2PBuotgRTHzEa8NeUmM/z+gcwIboTmS/JHc+EHJQos 5p/YawPuN7/rvWdjjx3jTRYLQjV3ty/Nk3SQWZVCsqoFJT2QLdi6Qf8Nr1TCPgyVrka7Sm JqB6dZWVRnatSsi46SYos3/d9ArAIlQ= X-Stat-Signature: cd5ux5weqtuk9kzmpkm6fskzyy713o1n X-Rspamd-Queue-Id: 2EB53A0008 X-Rspamd-Server: rspam01 X-Rspam-User: Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b="TvL+I/WO"; spf=pass (imf15.hostedemail.com: domain of keescook@chromium.org designates 209.85.210.176 as permitted sender) smtp.mailfrom=keescook@chromium.org; dmarc=pass (policy=none) header.from=chromium.org X-HE-Tag: 1668743522-165345 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: As already done for kmalloc_node(), clean up the #ifdef usage in the definition of kmalloc() so that the SLOB-only version is an entirely separate and much more readable function. Cc: Vlastimil Babka Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: Roman Gushchin Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Signed-off-by: Kees Cook Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> --- include/linux/slab.h | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 1c670c16c737..9033937c758e 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -558,15 +558,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align * Try really hard to succeed the allocation but fail * eventually. */ +#ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) { if (__builtin_constant_p(size)) { -#ifndef CONFIG_SLOB unsigned int index; -#endif + if (size > KMALLOC_MAX_CACHE_SIZE) return kmalloc_large(size, flags); -#ifndef CONFIG_SLOB + index = kmalloc_index(size); if (!index) @@ -575,10 +575,18 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) return kmalloc_trace( kmalloc_caches[kmalloc_type(flags)][index], flags, size); -#endif } return __kmalloc(size, flags); } +#else +static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) +{ + if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE) + return kmalloc_large(size, flags); + + return __kmalloc(size, flags); +} +#endif #ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) From patchwork Fri Nov 18 03:51:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 13047692 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B2408C43217 for ; Fri, 18 Nov 2022 03:52:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C19C56B0078; Thu, 17 Nov 2022 22:52:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BCADD8E0002; Thu, 17 Nov 2022 22:52:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9CE878E0001; Thu, 17 Nov 2022 22:52:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 885A96B0078 for ; Thu, 17 Nov 2022 22:52:04 -0500 (EST) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 69E001C5DFD for ; Fri, 18 Nov 2022 03:52:04 +0000 (UTC) X-FDA: 80145189768.10.4B08C13 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) by imf27.hostedemail.com (Postfix) with ESMTP id 075C340011 for ; Fri, 18 Nov 2022 03:52:02 +0000 (UTC) Received: by mail-pf1-f176.google.com with SMTP id k15so3750191pfg.2 for ; Thu, 17 Nov 2022 19:52:02 -0800 (PST) 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 :message-id:reply-to; bh=13POlA7CELUjT6ZjE2YlVT7xlxRT3lU0xqTeymXfKuQ=; b=mln/mgTD/8ZiYnrfEL5sJdItSGA3CsUZXe0Rbw9VmgWwP7++319wUWFlXAOZhmdkE+ Q1A8F59QiRmh/VDbUqCYA2L/XIIyIXNDrRkekGA+mdDaZnqnT7Iacfw8H/f5UlHKWNFL zWFpNrCeB4pUtxOC9D7mAQUfGrSn4vB3tbBI4= 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:message-id:reply-to; bh=13POlA7CELUjT6ZjE2YlVT7xlxRT3lU0xqTeymXfKuQ=; b=eekXYxpf1i5sIn9M6nKJQPSOvJWv9rL4y5/Jhd34uiEhXVjEpx9eh6JfOQ2v2XOsAX VXohVIfMTWxa6Wzw7a/fbWB3vZ8lzZTfFibdQL0kkpFIUQXeCG6n1JrgRbplwkIisLZE vYBifN5LDuM7nhOCOk0MHEH7JFgPBVVQFsrIvT4G8M0WlhnN473XCGzv3tbR+cCsCBqT JWYQ9eVsBr7pK898R8ILepvrfDXPAFeFs6MoJ1Bo2KYRp+n/pnOInhOzDozN0A4xQ6hh CPnfPLSJVAqKayMCjeqopKGFxulQXCimwMwUqjiwkLuzPiF+FdIk1td2itliC9DwSWp6 x4Rg== X-Gm-Message-State: ANoB5pk4QP1a37cw6+khaWdbnFIZ5y6zKeoZ1FAPUey58Lsfo6lsgrgg t+38dw1HW1c4d8Jx2nXoHPrTcQ== X-Google-Smtp-Source: AA0mqf6N+OlYszLxbtmqYFwWBrZKb2ySfrwYomT8syL2s6d6kloyN/S01vclXkdw4lKt9+nfwwJ+dw== X-Received: by 2002:a65:6847:0:b0:476:f43e:a86 with SMTP id q7-20020a656847000000b00476f43e0a86mr4988332pgt.363.1668743522032; Thu, 17 Nov 2022 19:52:02 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id u18-20020a170902e5d200b00186748fe6ccsm2276693plf.214.2022.11.17.19.52.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 19:52:01 -0800 (PST) From: Kees Cook To: Vlastimil Babka Cc: Kees Cook , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 2/2] slab: Remove special-casing of const 0 size allocations Date: Thu, 17 Nov 2022 19:51:59 -0800 Message-Id: <20221118035200.1269184-2-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221118034713.gonna.754-kees@kernel.org> References: <20221118034713.gonna.754-kees@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2371; h=from:subject; bh=roYcJKurZ1Ad0yqcM7lIDF6nN9ThBNp448RHSIPN1YQ=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBjdwFfZxDK7dz/ZV+GaTBVSw8vUtlA5Z9lYg4dYZxh Ty2FDZaJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCY3cBXwAKCRCJcvTf3G3AJqB3D/ 92I8BImb3l8xp7T7C/K708vzPl/8cg+RmpOK6O8J9tqppE4B5M+SHEFIwWoiPjeSunOrFQ1DwDx9iZ u69XcPWH0rvSq6XgAS4hKKx3hUEvm7SfHhU/tMqqLMduePCXfFRifcSHXyzlATJyq8Wouii8HIaWo4 wpwfW8/jeErjZCLwxoOQFfOGSdrPISOLAvnII7IHQyoHd/w0i9HLKgRHtB8xe4z9u/B0X33zioYBJN J62lW7fZXdQJey/y170LtBc8LAW/Tw7fwE8hxD0AsbzzOxgYShr8FnHhwwcu0EC4j4GnYBuTey8frV EySb8ats1/DK6YD0YCsS5AQB+/IUERCstiwsPOzLUZgZd8bdSusAxZhGH4iBRRof6wHWXGNrjAVwhn 3Snjp2O9GaBhJWiCAuNsthWjbSRE5KabMfNcSbunYrPfQXvBCXcdsUNxPVAILnJG2RgVexDJXdP1+S 95JSp0z6rrSxXhOefnmqdca5dura/qA18ttumMHL/6w2vykG0fx4VLfMizyQgi3/yTu9ykaTsw77+6 /VGws3PmhsMC0P+WacnTRQRezboPQxcBN65EO5en1ch1MUhYl6E+/yKf9e6POwUMv6e8aO56MI3us9 C/kaUdRHt4xCbf/FUTiy6plT2ZYVnNHudbi4m84b46NIo/ancm1AFn8JpH1A== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1668743523; a=rsa-sha256; cv=none; b=Hh/3OnyXZKukM+8Zxjruwz68qOoV1YsImjqB/S4vxYJAkASWf9+gjF6We5M/QdRMf7lb/F P1aIKIRtgbGjCgL/f0uhuNbw6DkrgGFn45mRNb4LJ823CjtrvnAUDEph5sa7oR9TEbUoW+ ywn+wCNszcWIiShr2Jj536tjQ3KRoRo= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b="mln/mgTD"; dmarc=pass (policy=none) header.from=chromium.org; spf=pass (imf27.hostedemail.com: domain of keescook@chromium.org designates 209.85.210.176 as permitted sender) smtp.mailfrom=keescook@chromium.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668743523; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=13POlA7CELUjT6ZjE2YlVT7xlxRT3lU0xqTeymXfKuQ=; b=Nj/6K/h7vjj6dGypSDoDBhNNJcC3e4zK3N8TDaWWJ2jllYvJNA35eaF6RO2Qk7gCLrGQdU 3AbStmpfjzVcZM7Xk2PCc96Yc7sXnoXLp3v4Jr9X8fQ5uzGJymsauzEJo1j6R5rxG6vZxW 4PFBvIWiR6icYeFwLtGTe5GvK44gIJQ= X-Stat-Signature: ujmn9d1wxy8cp96es5h4zyomzq5wqjxe X-Rspamd-Queue-Id: 075C340011 Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b="mln/mgTD"; dmarc=pass (policy=none) header.from=chromium.org; spf=pass (imf27.hostedemail.com: domain of keescook@chromium.org designates 209.85.210.176 as permitted sender) smtp.mailfrom=keescook@chromium.org X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1668743522-689431 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: Passing a constant-0 size allocation into kmalloc() or kmalloc_node() does not need to be a fast-path operation, so the static return value can be removed entirely. This is in preparation for making sure that all paths through the inlines result in a full extern function call, where __alloc_size() hints will actually be seen[1] by GCC. (A constant return value of 0 means the "0" allocation size won't be propagated by the inline.) [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96503 Cc: Vlastimil Babka Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: Roman Gushchin Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Signed-off-by: Kees Cook Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> --- include/linux/slab.h | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 9033937c758e..84be05208418 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -561,17 +561,13 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node) __assume_page_align #ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) { - if (__builtin_constant_p(size)) { + if (__builtin_constant_p(size) && size) { unsigned int index; if (size > KMALLOC_MAX_CACHE_SIZE) return kmalloc_large(size, flags); index = kmalloc_index(size); - - if (!index) - return ZERO_SIZE_PTR; - return kmalloc_trace( kmalloc_caches[kmalloc_type(flags)][index], flags, size); @@ -591,17 +587,13 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags) #ifndef CONFIG_SLOB static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node) { - if (__builtin_constant_p(size)) { + if (__builtin_constant_p(size) && size) { unsigned int index; if (size > KMALLOC_MAX_CACHE_SIZE) return kmalloc_large_node(size, flags, node); index = kmalloc_index(size); - - if (!index) - return ZERO_SIZE_PTR; - return kmalloc_node_trace( kmalloc_caches[kmalloc_type(flags)][index], flags, node, size);