mm/vmalloc: add __alloc_size attributes for better bounds checking

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.

Link: https://lkml.kernel.org/r/20210930222704.2631604-7-keescook@chromium.orgSigned-off-by: NKees Cook <keescook@chromium.org>
Co-developed-by: NDaniel Micay <danielmicay@gmail.com>
Signed-off-by: NDaniel Micay <danielmicay@gmail.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jing Xiangfeng <jingxiangfeng@huawei.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/vmalloc.h

@@ -136,21 +136,21 @@ static inline void vmalloc_init(void)
 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
 #endif
 
-extern void *vmalloc(unsigned long size);
-extern void *vzalloc(unsigned long size);
-extern void *vmalloc_user(unsigned long size);
-extern void *vmalloc_node(unsigned long size, int node);
-extern void *vzalloc_node(unsigned long size, int node);
-extern void *vmalloc_32(unsigned long size);
-extern void *vmalloc_32_user(unsigned long size);
-extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
+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);
+			const void *caller) __alloc_size(1);
 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
-		int node, const void *caller);
-void *vmalloc_no_huge(unsigned long size);
+		int node, const void *caller) __alloc_size(1);
+void *vmalloc_no_huge(unsigned long size) __alloc_size(1);
 
 extern void vfree(const void *addr);
 extern void vfree_atomic(const void *addr);