From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f173.google.com (mail-pl1-f173.google.com [209.85.214.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BCE951101 for ; Sat, 5 Nov 2022 01:09:41 +0000 (UTC) Received: by mail-pl1-f173.google.com with SMTP id p12so875627plq.4 for ; Fri, 04 Nov 2022 18:09:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; 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=UZRKTfzUgUmUoDMmXtLNWbH1d7SRg9NOYtTV2ieREGk=; b=WEeQ3oedxebSq3TylgaXd4uhHZ9fSf85t4y+VbXKEnRu/7HDBOu+78DX1+z7CCi5y7 iXRQ9RG1+Zg01X1PRF7ztSjuRtPSWejAzJyKjVmW5vQBGjgN+PSGGvaFgNrjYR/yHXLH sn53T4Ne/NmwBRYJ5cRZM4YACVxoe+c7TnndsA9ak7FT4Nk/uRjxeR9Kgv2Ji9Kwf4GZ ZSwkypKIL9HoKD6Va65PrJYvi1yFVSeWLvEEoMsWeLDq5B7KPzuGinuq4ql9AMXKXWPu tMeggNh/G7KLz4CDnMCUtPkiNqH/satSpu6aMojsrEmZbKZLfg2X2ZK94qwSx3yGOOOC l90A== 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=UZRKTfzUgUmUoDMmXtLNWbH1d7SRg9NOYtTV2ieREGk=; b=uaPfoSPjO9IwOZRve+RkqLzmd3q6dPOeemvFf4KlJiwmYvt7SifeuXo/rwWRcclYhq mbIJS9wdkoQvOFwdNTP92TL+EgrneYfwV5gMAFsalkG3tBL9+aoFuA3szszVyG18iO1u nSTe8gs8CsRSoCKmSzw3Zx6/eaoWRxbIncYhSzF6YF7OLkYLhI0zc8MXEJJYCDgICwIj EjoBmdVnxtxxkTPmagRe4sQInrUwkwSHhWSuWy2l31gEkZNpkxqaRx4QPM+L/kdF5AmN S7XvpQBdZx6973VMUd41WT7UCnXJctUrc/i/I5uWJRQ0AMdLIxOKmGdGqi2IOX8qtcfe ibSw== X-Gm-Message-State: ACrzQf0E+uf6gP3eVHDuifJvGUVY4EvMDmeMsteEREKhyZtj33sBzhuJ h1FTiuP99VKmLE6hAtP4/a4= X-Google-Smtp-Source: AMsMyM7rn2BtRhnzi3h+OsA0B40E06ImoWbABI8HcmyJhN73GZyM7ao3+XvXzCg/8TYVD9EkwCIrNg== X-Received: by 2002:a17:90a:ba85:b0:212:d644:fc28 with SMTP id t5-20020a17090aba8500b00212d644fc28mr39973129pjr.72.1667610581148; Fri, 04 Nov 2022 18:09:41 -0700 (PDT) Received: from hyeyoo ([114.29.91.56]) by smtp.gmail.com with ESMTPSA id u7-20020a63ef07000000b004393c5a8006sm310615pgh.75.2022.11.04.18.09.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Nov 2022 18:09:40 -0700 (PDT) Date: Sat, 5 Nov 2022 10:09:32 +0900 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> To: Kees Cook 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: References: <20221101222520.never.109-kees@kernel.org> <20221101223321.1326815-3-keescook@chromium.org> <202211041121.2F1639D2@keescook> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202211041121.2F1639D2@keescook> 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 Thanks! -- Hyeonggon