Commit 20e5cc26 authored by Kees Cook's avatar Kees Cook
Browse files

compiler.h: Introduce __must_be_byte_array() 



In preparation for adding stricter type checking to the str/mem*()
helpers, provide a way to check that a variable is a byte array
via __must_be_byte_array().

Suggested-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: default avatarKees Cook <kees@kernel.org>
parent cb7380de

include/linux/compiler.h

+7 −1
Original line number Diff line number Diff line
@@ -221,7 +221,13 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, 
#endif /* __CHECKER__ */



/* &a[0] degrades to a pointer: a different type from an array */

#define __must_be_array(a)	__BUILD_BUG_ON_ZERO_MSG(__same_type((a), &(a)[0]), "must be array")

#define __is_array(a)		(!__same_type((a), &(a)[0]))

#define __must_be_array(a)	__BUILD_BUG_ON_ZERO_MSG(!__is_array(a), \

							"must be array")



#define __is_byte_array(a)	(__is_array(a) && sizeof((a)[0]) == 1)

#define __must_be_byte_array(a)	__BUILD_BUG_ON_ZERO_MSG(!__is_byte_array(a), \

							"must be byte array")



/* Require C Strings (i.e. NUL-terminated) lack the "nonstring" attribute. */

#define __must_be_cstr(p) \