Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-15 21:23:23 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

compiler.h: Fix undefined BUILD_BUG_ON_ZERO()

Browse Source 
<linux/compiler.h> defines __must_be_array() and __must_be_cstr() and
both expand to BUILD_BUG_ON_ZERO(), but <linux/build_bug.h> defines
BUILD_BUG_ON_ZERO(). Including <linux/build_bug.h> in
<linux/compiler.h> would create a cyclic dependency as
<linux/build_bug.h> already includes <linux/compiler.h>.

Fix that by defining __BUILD_BUG_ON_ZERO_MSG() in <linux/compiler.h>
and using that for __must_be_array() and __must_be_cstr().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Link: https://lore.kernel.org/r/20241115204602.249590-1-philipp.reisner@linbit.com
Signed-off-by: Kees Cook <kees@kernel.org>
This commit is contained in:
Philipp Reisner 2024-11-15 21:46:02 +01:00 committed by Kees Cook
parent a508ef4b1d
commit d7a516c6ee
1 changed files with 9 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
include/linux/compiler.h
View File

@ -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