From mboxrd@z Thu Jan 1 00:00:00 1970 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 A288BC433FE for ; Sat, 5 Nov 2022 06:46:03 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 00DBD8E0001; Sat, 5 Nov 2022 02:46:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F00BC6B0073; Sat, 5 Nov 2022 02:46:02 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DC8EE8E0001; Sat, 5 Nov 2022 02:46:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id CE8D46B0071 for ; Sat, 5 Nov 2022 02:46:02 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id A05261C603B for ; Sat, 5 Nov 2022 06:46:02 +0000 (UTC) X-FDA: 80098453764.04.DED1248 Received: from mail-pj1-f53.google.com (mail-pj1-f53.google.com [209.85.216.53]) by imf14.hostedemail.com (Postfix) with ESMTP id 2BDE9100002 for ; Sat, 5 Nov 2022 06:46:01 +0000 (UTC) Received: by mail-pj1-f53.google.com with SMTP id u8-20020a17090a5e4800b002106dcdd4a0so10108010pji.1 for ; Fri, 04 Nov 2022 23:46:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=srq0262QxbkEV6kNYP4erFtvI0rgH+oqu5/TPMxlwy4=; b=W4KaJP6FV2vwHiDT+VvgaGaA1jeM6SQ8YJpGYx2Pbkhvyt+b8ut77tl012BXpoCSKZ u+nxM1dLCKIVpLHfyXG1p88984BbMhKZGcd9C4F0RT8kncpFr41iKYeXmFz2HFf1Qd2/ RsyWHfwKmiA0qvv+5iNwqot7JBpHFX9AjApgU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=srq0262QxbkEV6kNYP4erFtvI0rgH+oqu5/TPMxlwy4=; b=KUqbVaSwTtZtKU8KDoN2vW99Jq6gMGkvy+k9/KBYR2Ex80KFQXlKAu3EJHckGpsT2n LiXkV9jk8f9HVMbkC8O294J3kIE9Qbzs6ptqB53XH3y9cKSRYJA8VrPXPI04FweA5Y7e QFuCn7Z1t8Qy/pIgcq7VRb+oHTN4fGeMqXschoP3/JpXexZ2G7KTb26TsNzH7blp+GX7 RpSJ9rnxSy35OzP74NWSv4lrDQwU9eUijOQtWNlTUIAJQ87CDa8C6TdTgeEL7r0l4xWo jQZz4xLCxvxffacEys3K8j8+nNzuUkiGGTLxFlAAXAQrXwFzLW2qIwO8kux7mDpBcQA7 W5Iw== X-Gm-Message-State: ACrzQf0OCjlUWmb7bv9L+J64SUw5v1/ydvo60q3MJb6iyyvJwRiRwNPH WQ4uSOTAcsPVIfSCslkit9CG1Q== X-Google-Smtp-Source: AMsMyM4oJjpqJJcKwUVLP7X5WeicCqIX6jcTy1xHjHbJtoU/3/GvJrm+L6ClZGrmleAPy813oxTJNQ== X-Received: by 2002:a17:903:1c6:b0:185:47ce:f4f0 with SMTP id e6-20020a17090301c600b0018547cef4f0mr40384496plh.132.1667630761129; Fri, 04 Nov 2022 23:46:01 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id n2-20020a170902d2c200b0018099c9618esm857879plc.231.2022.11.04.23.46.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Nov 2022 23:46:00 -0700 (PDT) Date: Fri, 4 Nov 2022 23:45:59 -0700 From: Kees Cook To: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Vlastimil Babka , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Roman Gushchin , linux-mm@kvack.org, David Gow , Rasmus Villemoes , Guenter Roeck , Andy Shevchenko , Paolo Abeni , Geert Uytterhoeven , Nathan Chancellor , Nick Desaulniers , Tom Rix , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH 3/6] slab: Provide functional __alloc_size() hints to kmalloc_trace*() Message-ID: <202211042345.B1D74469BC@keescook> References: <20221101222520.never.109-kees@kernel.org> <20221101223321.1326815-3-keescook@chromium.org> <202211041121.2F1639D2@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1667630762; a=rsa-sha256; cv=none; b=sCy652XbGzcZz6qeip4FqHUVVO94X9g203yBTsqeWfI7fCbYGEJjcQxPAcZhvG69rZ41KJ fjPpO2U1ppriPXTbObtS37U7lVnnCJXgLITipLdlEJdgx1Vi399mzTr5lqe9zEvTv2dK0d p7Cf7ReBpO4nGUpQ5rjf2vdV7Qrn4pQ= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=W4KaJP6F; spf=pass (imf14.hostedemail.com: domain of keescook@chromium.org designates 209.85.216.53 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=1667630762; 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-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=srq0262QxbkEV6kNYP4erFtvI0rgH+oqu5/TPMxlwy4=; b=X6FwZ4a9LTkENkl10cqaJ7SkWjcjY2lnp6A1YhSbPMiu6gc38VjZd39chCEVDrgxs0o+4K 3lZB08wcPp/c+0O42wbEReFE8zMMO/HdaK7/lOauhFPYWnT/cmPKRN0yFQy4ZU8hM7H8e4 Ndc22csk13CDDfXHfNga5U1ZdMv0AkA= Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=W4KaJP6F; spf=pass (imf14.hostedemail.com: domain of keescook@chromium.org designates 209.85.216.53 as permitted sender) smtp.mailfrom=keescook@chromium.org; dmarc=pass (policy=none) header.from=chromium.org X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 2BDE9100002 X-Stat-Signature: 1ddhdran6zc4dyyct1r8kkujp154p7tb X-HE-Tag: 1667630761-360264 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: On Sat, Nov 05, 2022 at 10:09:32AM +0900, Hyeonggon Yoo wrote: > On Fri, Nov 04, 2022 at 11:22:42AM -0700, Kees Cook wrote: > > On Thu, Nov 03, 2022 at 11:16:53PM +0900, Hyeonggon Yoo wrote: > > > On Tue, Nov 01, 2022 at 03:33:11PM -0700, Kees Cook wrote: > > > > Since GCC cannot apply the __alloc_size attributes to inlines[1], all > > > > allocator inlines need to explicitly call into extern functions that > > > > contain a size argument. Provide these wrappers that end up just > > > > ignoring the size argument for the actual allocation. > > > > > > > > This allows CONFIG_FORTIFY_SOURCE=y to see all various dynamic allocation > > > > sizes under GCC 12+ and all supported Clang versions. > > > > > > > > [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 > > > > --- > > > > include/linux/slab.h | 8 ++++++-- > > > > mm/slab_common.c | 14 ++++++++++++++ > > > > 2 files changed, 20 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/include/linux/slab.h b/include/linux/slab.h > > > > index 970e9504949e..051d86ca31a8 100644 > > > > --- a/include/linux/slab.h > > > > +++ b/include/linux/slab.h > > > > @@ -442,6 +442,8 @@ static_assert(PAGE_SHIFT <= 20); > > > > > > > > void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); > > > > void *kmem_cache_alloc(struct kmem_cache *s, gfp_t flags) __assume_slab_alignment __malloc; > > > > +void *kmem_cache_alloc_sized(struct kmem_cache *s, gfp_t flags, size_t size) > > > > + __assume_slab_alignment __alloc_size(3); > > > > void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, > > > > gfp_t gfpflags) __assume_slab_alignment __malloc; > > > > void kmem_cache_free(struct kmem_cache *s, void *objp); > > > > @@ -469,6 +471,8 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignm > > > > __alloc_size(1); > > > > void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node) __assume_slab_alignment > > > > __malloc; > > > > +void *kmem_cache_alloc_node_sized(struct kmem_cache *s, gfp_t flags, int node, size_t size) > > > > + __assume_slab_alignment __alloc_size(4); > > > > > > > > #ifdef CONFIG_TRACING > > > > void *kmalloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) > > > > @@ -482,7 +486,7 @@ void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, > > > > static __always_inline __alloc_size(3) > > > > void *kmalloc_trace(struct kmem_cache *s, gfp_t flags, size_t size) > > > > { > > > > - void *ret = kmem_cache_alloc(s, flags); > > > > + void *ret = kmem_cache_alloc_sized(s, flags, size); > > > > > > > > ret = kasan_kmalloc(s, ret, size, flags); > > > > return ret; > > > > @@ -492,7 +496,7 @@ static __always_inline __alloc_size(4) > > > > void *kmalloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, > > > > int node, size_t size) > > > > { > > > > - void *ret = kmem_cache_alloc_node(s, gfpflags, node); > > > > + void *ret = kmem_cache_alloc_node_sized(s, gfpflags, node, size); > > > > > > > > ret = kasan_kmalloc(s, ret, size, gfpflags); > > > > return ret; > > > > diff --git a/mm/slab_common.c b/mm/slab_common.c > > > > index 33b1886b06eb..5fa547539a6a 100644 > > > > --- a/mm/slab_common.c > > > > +++ b/mm/slab_common.c > > > > @@ -1457,6 +1457,20 @@ size_t ksize(const void *objp) > > > > } > > > > EXPORT_SYMBOL(ksize); > > > > > > > > +/* Wrapper so __alloc_size() can see the actual allocation size. */ > > > > +void *kmem_cache_alloc_sized(struct kmem_cache *s, gfp_t flags, size_t size) > > > > +{ > > > > + return kmem_cache_alloc(s, flags); > > > > +} > > > > +EXPORT_SYMBOL(kmem_cache_alloc_sized); > > > > + > > > > +/* Wrapper so __alloc_size() can see the actual allocation size. */ > > > > +void *kmem_cache_alloc_node_sized(struct kmem_cache *s, gfp_t flags, int node, size_t size) > > > > +{ > > > > + return kmem_cache_alloc_node(s, flags, node); > > > > +} > > > > +EXPORT_SYMBOL(kmem_cache_alloc_node_sized); > > > > > > The reason that we have two implementations of kmalloc_trace* > > > depending on CONFIG_TRACING is to save additional function call when > > > CONFIG_TRACING is not set. > > > > > > With this patch there is no reason to keep both. > > > So let's drop #ifdefs and use single implementation in mm/slab_common.c. > > > > Okay, I'll respin... > > > > -- > > Kees Cook > > Oh, it seems Vlastimil already did that. > Maybe simply drop this patch in next spin? > > https://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git/commit/?h=slab/for-6.1-rc4/fixes&id=eb4940d4adf590590a9d0c47e38d2799c2ff9670 Oh! Well, yes, that makes that easy. :) -- Kees Cook