Commit 5ac86f0e authored by Kees Cook's avatar Kees Cook
Browse files

virt: vbox: struct vmmdev_hgcm_pagelist: Replace 1-element array with flexible array 

Replace the deprecated[1] use of a 1-element array in
struct vmmdev_hgcm_pagelist with a modern flexible array. As this is
UAPI, we cannot trivially change the size of the struct, so use a union
to retain the old first element's size, but switch "pages" to a flexible
array.

No binary differences are present after this conversion.

Link: https://github.com/KSPP/linux/issues/79

 [1]
Reviewed-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240710231555.work.406-kees@kernel.org


Signed-off-by: default avatarKees Cook <kees@kernel.org>
parent bbf3c7ff

include/uapi/linux/vbox_vmmdev_types.h

+4 −1
Original line number Diff line number Diff line
@@ -282,7 +282,10 @@ struct vmmdev_hgcm_pagelist { 
	__u32 flags;             /** VMMDEV_HGCM_F_PARM_*. */

	__u16 offset_first_page; /** Data offset in the first page. */

	__u16 page_count;        /** Number of pages. */

	__u64 pages[1];          /** Page addresses. */

	union {

		__u64 unused;	/** Deprecated place-holder for first "pages" entry. */

		__DECLARE_FLEX_ARRAY(__u64, pages); /** Page addresses. */

	};

};

VMMDEV_ASSERT_SIZE(vmmdev_hgcm_pagelist, 4 + 2 + 2 + 8);