diff options
author | Ian Jackson <ian.jackson@eu.citrix.com> | 2013-06-14 16:45:36 +0100 |
---|---|---|
committer | Ian Jackson <Ian.Jackson@eu.citrix.com> | 2013-06-14 16:45:36 +0100 |
commit | bbf40e6b6d47809f4289a866d7d167c25104ecc0 (patch) | |
tree | efb73be0dd29bb7246c75b67f6c5d2e1ef35265f /tools | |
parent | 64a0206c451920b72a9c5721a6f2427baf99e3dd (diff) | |
download | xen-bbf40e6b6d47809f4289a866d7d167c25104ecc0.tar.gz xen-bbf40e6b6d47809f4289a866d7d167c25104ecc0.tar.bz2 xen-bbf40e6b6d47809f4289a866d7d167c25104ecc0.zip |
libxc: introduce xc_dom_seg_to_ptr_pages
Provide a version of xc_dom_seg_to_ptr which returns the number of
guest pages it has actually mapped. This is useful for callers who
want to do range checking; we will use this later in this series.
This is part of the fix to a security issue, XSA-55.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/libxc/xc_dom.h | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/tools/libxc/xc_dom.h b/tools/libxc/xc_dom.h index 7043f96752..19a10f42e8 100644 --- a/tools/libxc/xc_dom.h +++ b/tools/libxc/xc_dom.h @@ -262,14 +262,27 @@ void *xc_dom_pfn_to_ptr(struct xc_dom_image *dom, xen_pfn_t first, void xc_dom_unmap_one(struct xc_dom_image *dom, xen_pfn_t pfn); void xc_dom_unmap_all(struct xc_dom_image *dom); -static inline void *xc_dom_seg_to_ptr(struct xc_dom_image *dom, - struct xc_dom_seg *seg) +static inline void *xc_dom_seg_to_ptr_pages(struct xc_dom_image *dom, + struct xc_dom_seg *seg, + xen_pfn_t *pages_out) { xen_vaddr_t segsize = seg->vend - seg->vstart; unsigned int page_size = XC_DOM_PAGE_SIZE(dom); xen_pfn_t pages = (segsize + page_size - 1) / page_size; + void *retval; + + retval = xc_dom_pfn_to_ptr(dom, seg->pfn, pages); + + *pages_out = retval ? pages : 0; + return retval; +} + +static inline void *xc_dom_seg_to_ptr(struct xc_dom_image *dom, + struct xc_dom_seg *seg) +{ + xen_pfn_t dummy; - return xc_dom_pfn_to_ptr(dom, seg->pfn, pages); + return xc_dom_seg_to_ptr_pages(dom, seg, &dummy); } static inline void *xc_dom_vaddr_to_ptr(struct xc_dom_image *dom, |