With the coming support for the __counted_by struct member attribute, we will need a way to add such annotations to the places where DECLARE_FLEX_ARRAY() is used. Introduce DECLARE_FLEX_ARRAY_ATTR() which takes a third argument: the attributes to apply to the flexible array.
Cc: Gustavo A. R. Silva <[email protected]> Cc: Rasmus Villemoes <[email protected]> Cc: Dan Williams <[email protected]> Cc: Keith Packard <[email protected]> Cc: Miguel Ojeda <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Dmitry Antipov <[email protected]> Signed-off-by: Kees Cook <[email protected]> --- include/linux/stddef.h | 16 ++++++++++++++-- include/uapi/linux/stddef.h | 25 +++++++++++++++++++------ 2 files changed, 33 insertions(+), 8 deletions(-) diff --git a/include/linux/stddef.h b/include/linux/stddef.h index 929d67710cc5..eb51f6727ecf 100644 --- a/include/linux/stddef.h +++ b/include/linux/stddef.h @@ -81,8 +81,20 @@ enum { __struct_group(TAG, NAME, /* no attrs */, MEMBERS) /** - * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * DECLARE_FLEX_ARRAY_ATTR() - Declare a flexible array usable in a union + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * @ATTRS: The list of member attributes to apply * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) + +/** + * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union * @TYPE: The type of each flexible array element * @NAME: The name of the flexible array member * @@ -91,6 +103,6 @@ enum { * named member, but that member can be empty. */ #define DECLARE_FLEX_ARRAY(TYPE, NAME) \ - __DECLARE_FLEX_ARRAY(TYPE, NAME) + DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #endif diff --git a/include/uapi/linux/stddef.h b/include/uapi/linux/stddef.h index 2ec6f35cda32..5499c08ad011 100644 --- a/include/uapi/linux/stddef.h +++ b/include/uapi/linux/stddef.h @@ -31,24 +31,37 @@ #ifdef __cplusplus /* sizeof(struct{}) is 1 in C++, not 0, can't use C version of the macro. */ -#define __DECLARE_FLEX_ARRAY(T, member) \ - T member[0] +#define __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ + TYPE NAME[0] ATTRS +#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #else /** - * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union - * + * __DECLARE_FLEX_ARRAY_ATTR() - Declare a flexible array usable in a union * @TYPE: The type of each flexible array element * @NAME: The name of the flexible array member + * @ATTRS: The list of member attributes to apply * * In order to have a flexible array member in a union or alone in a * struct, it needs to be wrapped in an anonymous struct with at least 1 * named member, but that member can be empty. */ -#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ +#define __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ struct { \ struct { } __empty_ ## NAME; \ - TYPE NAME[]; \ + TYPE NAME[] ATTRS; \ } +/** + * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #endif #ifndef __counted_by -- 2.34.1
