Commit 36843bfb authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'hardening-v6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux 

Pull hardening updates from Kees Cook:

 - Disable __counted_by in Clang < 19.1.3 (Jan Hendrik Farr)

 - string_helpers: Silence output truncation warning (Bartosz
   Golaszewski)

 - compiler.h: Avoid needing BUILD_BUG_ON_ZERO() (Philipp Reisner)

 - MAINTAINERS: Add kernel hardening keywords __counted_by{_le|_be}
   (Thorsten Blum)

* tag 'hardening-v6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  Compiler Attributes: disable __counted_by for clang < 19.1.3
  compiler.h: Fix undefined BUILD_BUG_ON_ZERO()
  lib: string_helpers: silence snprintf() output truncation warning
  MAINTAINERS: Add kernel hardening keywords __counted_by{_le|_be}
parents 573f45a9 f06e108a

MAINTAINERS

+1 −1
Original line number Diff line number Diff line
@@ -12403,7 +12403,7 @@ F: mm/usercopy.c 
F:	security/Kconfig.hardening

K:	\b(add|choose)_random_kstack_offset\b

K:	\b__check_(object_size|heap_object)\b

K:	\b__counted_by\b

K:	\b__counted_by(_le|_be)?\b









KERNEL JANITORS









L:	kernel-janitors@vger.kernel.org
































drivers/misc/lkdtm/bugs.c



+1
−1






























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@@ -445,7 +445,7 @@ static void lkdtm_FAM_BOUNDS(void)

















	pr_err("FAIL: survived access of invalid flexible array member index!\n");



















	if (!__has_attribute(__counted_by__))









	if (!IS_ENABLED(CONFIG_CC_HAS_COUNTED_BY))









		pr_warn("This is expected since this %s was built with a compiler that does not support __counted_by\n",









			lkdtm_kernel_info);









	else if (IS_ENABLED(CONFIG_UBSAN_BOUNDS))
































include/linux/compiler.h



+9
−2






























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@@ -239,11 +239,18 @@ static inline void *offset_to_ptr(const int *off)

















#endif /* __ASSEMBLY__ */



















#ifdef __CHECKER__









#define __BUILD_BUG_ON_ZERO_MSG(e, msg) (0)









#else /* __CHECKER__ */









#define __BUILD_BUG_ON_ZERO_MSG(e, msg) ((int)sizeof(struct {_Static_assert(!(e), msg);}))









#endif /* __CHECKER__ */



















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









#define __must_be_array(a)	BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))









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



















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









#define __must_be_cstr(p)	BUILD_BUG_ON_ZERO(__annotated(p, nonstring))









#define __must_be_cstr(p) \









	__BUILD_BUG_ON_ZERO_MSG(__annotated(p, nonstring), "must be cstr (NUL-terminated)")



















/*









 * This returns a constant expression while determining if an argument is
































include/linux/compiler_attributes.h



+0
−13






























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@@ -94,19 +94,6 @@







# define __copy(symbol)









#endif



















/*









 * Optional: only supported since gcc >= 15









 * Optional: only supported since clang >= 18









 *









 *   gcc: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108896









 * clang: https://github.com/llvm/llvm-project/pull/76348









 */









#if __has_attribute(__counted_by__)









# define __counted_by(member)		__attribute__((__counted_by__(member)))









#else









# define __counted_by(member)









#endif



















/*









 * Optional: not supported by gcc









 * Optional: only supported since clang >= 14.0
































include/linux/compiler_types.h



+19
−0






























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@@ -329,6 +329,25 @@ struct ftrace_likely_data {







#define __no_sanitize_or_inline __always_inline









#endif



















/*









 * Optional: only supported since gcc >= 15









 * Optional: only supported since clang >= 18









 *









 *   gcc: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108896









 * clang: https://github.com/llvm/llvm-project/pull/76348









 *









 * __bdos on clang < 19.1.2 can erroneously return 0:









 * https://github.com/llvm/llvm-project/pull/110497









 *









 * __bdos on clang < 19.1.3 can be off by 4:









 * https://github.com/llvm/llvm-project/pull/112636









 */









#ifdef CONFIG_CC_HAS_COUNTED_BY









# define __counted_by(member)		__attribute__((__counted_by__(member)))









#else









# define __counted_by(member)









#endif



















/*









 * Apply __counted_by() when the Endianness matches to increase test coverage.









 */