Commit c80d92fb authored by Kees Cook's avatar Kees Cook
Browse files

compiler_types.h: Remove __compiletime_object_size() 

Since all compilers support __builtin_object_size(), and there is only
one user of __compiletime_object_size, remove it to avoid the needless
indirection. This lets Clang reason about check_copy_size() correctly.

Link: https://github.com/ClangBuiltLinux/linux/issues/1179


Suggested-by: default avatarNick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: default avatarMiguel Ojeda <ojeda@kernel.org>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
parent 8610047c

include/linux/compiler-gcc.h

+0 −2
Original line number Diff line number Diff line
@@ -41,8 +41,6 @@ 


#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)



#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)



#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)

#define __latent_entropy __attribute__((latent_entropy))

#endif

include/linux/compiler_types.h

+0 −5
Original line number Diff line number Diff line
@@ -290,11 +290,6 @@ struct ftrace_likely_data { 
	(sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \

	 sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))



/* Compile time object size, -1 for unknown */

#ifndef __compiletime_object_size

# define __compiletime_object_size(obj) -1

#endif



#ifdef __OPTIMIZE__

# define __compiletime_assert(condition, msg, prefix, suffix)		\

	do {								\

include/linux/thread_info.h

+1 −1
Original line number Diff line number Diff line
@@ -203,7 +203,7 @@ static inline void copy_overflow(int size, unsigned long count) 
static __always_inline __must_check bool

check_copy_size(const void *addr, size_t bytes, bool is_source)

{

	int sz = __compiletime_object_size(addr);

	int sz = __builtin_object_size(addr, 0);

	if (unlikely(sz >= 0 && sz < bytes)) {

		if (!__builtin_constant_p(bytes))

			copy_overflow(sz, bytes);