string: Add __alloc_size hint to kmemdup()
Commit Message
Add __alloc_size() hint to kmemdup() so the compiler can reason about
the length of the returned buffer.
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
include/linux/fortify-string.h | 3 ++-
include/linux/string.h | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)
@@ -661,7 +661,8 @@ __FORTIFY_INLINE void *memchr_inv(const void * const POS0 p, int c, size_t size)
return __real_memchr_inv(p, c, size);
}
-extern void *__real_kmemdup(const void *src, size_t len, gfp_t gfp) __RENAME(kmemdup);
+extern void *__real_kmemdup(const void *src, size_t len, gfp_t gfp) __RENAME(kmemdup)
+ __alloc_size(2);
__FORTIFY_INLINE void *kmemdup(const void * const POS0 p, size_t size, gfp_t gfp)
{
size_t p_size = __struct_size(p);
@@ -176,7 +176,7 @@ extern void kfree_const(const void *x);
extern char *kstrdup(const char *s, gfp_t gfp) __malloc;
extern const char *kstrdup_const(const char *s, gfp_t gfp);
extern char *kstrndup(const char *s, size_t len, gfp_t gfp);
-extern void *kmemdup(const void *src, size_t len, gfp_t gfp);
+extern void *kmemdup(const void *src, size_t len, gfp_t gfp) __alloc_size(2);
extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp);
extern char **argv_split(gfp_t gfp, const char *str, int *argcp);