diff mbox

[v4,09/34] vmap: ASSERT on NULL.

Message ID 1458064616-23101-10-git-send-email-konrad.wilk@oracle.com (mailing list archive)
State New, archived
Headers show

Commit Message

Konrad Rzeszutek Wilk March 15, 2016, 5:56 p.m. UTC 
The vmap_to_page macro (three levels deep!) can come up with
a NULL pointer. Lets add the proper ASSERT to catch this errant
behavior.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

---
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
---
---
 xen/common/vmap.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/xen/common/vmap.c b/xen/common/vmap.c
index be01285..1f1da1b 100644
--- a/xen/common/vmap.c
+++ b/xen/common/vmap.c
@@ -279,8 +279,12 @@  void vfree(void *va)
     ASSERT(pages);
 
     for ( i = 0; i < pages; i++ )
-        page_list_add(vmap_to_page(va + i * PAGE_SIZE), &pg_list);
+    {
+        struct page_info *page = vmap_to_page(va + i * PAGE_SIZE);
 
+        ASSERT(page);
+        page_list_add(page, &pg_list);
+    }
     vunmap(va);
 
     while ( (pg = page_list_remove_head(&pg_list)) != NULL )