xen/gntalloc: Replace UAPI 1-element array

Without changing the structure size (since it is UAPI), add a proper
flexible array member, and reference it in the kernel so that it will
not be trip the array-bounds sanitizer[1].

Link: https://github.com/KSPP/linux/issues/113 [1]
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240206170320.work.437-kees@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Kees Cook
2024-02-06 09:03:24 -08:00
committed by Juergen Gross
parent b0f2f82c9c
commit bf5802238d
2 changed files with 5 additions and 2 deletions

View File

@@ -31,7 +31,10 @@ struct ioctl_gntalloc_alloc_gref {
__u64 index;
/* The grant references of the newly created grant, one per page */
/* Variable size, depending on count */
__u32 gref_ids[1];
union {
__u32 gref_ids[1];
__DECLARE_FLEX_ARRAY(__u32, gref_ids_flex);
};
};
#define GNTALLOC_FLAG_WRITABLE 1