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From:   Kees Cook <keescook@chromium.org>
To:     linux-kernel@vger.kernel.org
Cc:     Kees Cook <keescook@chromium.org>,
        Daniel Micay <danielmicay@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        Joe Perches <joe@perches.com>, Miguel Ojeda <ojeda@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Andy Whitcroft <apw@canonical.com>,
        Dwaipayan Ray <dwaipayanray1@gmail.com>,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Dennis Zhou <dennis@kernel.org>, Tejun Heo <tj@kernel.org>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Michal Marek <michal.lkml@markovi.net>,
        clang-built-linux@googlegroups.com, linux-kbuild@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: [PATCH v2 7/7] mm/vmalloc: Add __alloc_size attributes for better bounds checking
Date:   Wed, 18 Aug 2021 14:40:21 -0700
Message-Id: <20210818214021.2476230-8-keescook@chromium.org>
In-Reply-To: <20210818214021.2476230-1-keescook@chromium.org>
References: <20210818214021.2476230-1-keescook@chromium.org>
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As already done in GrapheneOS, add the __alloc_size attribute for
appropriate vmalloc allocator interfaces, to provide additional hinting
for better bounds checking, assisting CONFIG_FORTIFY_SOURCE and other
compiler optimizations.

Co-developed-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 include/linux/vmalloc.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 2644425b6dce..1521ba38957d 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -136,20 +136,31 @@ static inline void vmalloc_init(void)
 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
 #endif
 
+__alloc_size(1)
 extern void *vmalloc(unsigned long size);
+__alloc_size(1)
 extern void *vzalloc(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_user(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_node(unsigned long size, int node);
+__alloc_size(1)
 extern void *vzalloc_node(unsigned long size, int node);
+__alloc_size(1)
 extern void *vmalloc_32(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_32_user(unsigned long size);
+__alloc_size(1)
 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
+__alloc_size(1)
 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
 			unsigned long start, unsigned long end, gfp_t gfp_mask,
 			pgprot_t prot, unsigned long vm_flags, int node,
 			const void *caller);
+__alloc_size(1)
 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
 		int node, const void *caller);
+__alloc_size(1)
 void *vmalloc_no_huge(unsigned long size);
 
 extern void vfree(const void *addr);
-- 
2.30.2