[PATCH v2 7/7] mm/vmalloc: Add __alloc_size attributes for better bounds checking

[Kees Cook]

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@xxxxxxxxx>
Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 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