xen: set error code on failures

Variable rc is reset in the loop, and its value will be non-negative
during the second and after repeat of the loop. If it fails to allocate
memory then, it may return a non-negative integer, which indicates no
error. This patch fixes the bug, assigning "-ENOMEM" to rc when
kzalloc() or alloc_page() returns NULL, and removing the initialization
of rc outside of the loop.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Pan Bian 2016-12-05 16:23:05 +08:00 committed by Juergen Gross
parent 24d5373dda
commit 0fdb474402

View file

@ -127,18 +127,21 @@ static int add_grefs(struct ioctl_gntalloc_alloc_gref *op,
struct gntalloc_gref *gref, *next;
readonly = !(op->flags & GNTALLOC_FLAG_WRITABLE);
rc = -ENOMEM;
for (i = 0; i < op->count; i++) {
gref = kzalloc(sizeof(*gref), GFP_KERNEL);
if (!gref)
if (!gref) {
rc = -ENOMEM;
goto undo;
}
list_add_tail(&gref->next_gref, &queue_gref);
list_add_tail(&gref->next_file, &queue_file);
gref->users = 1;
gref->file_index = op->index + i * PAGE_SIZE;
gref->page = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (!gref->page)
if (!gref->page) {
rc = -ENOMEM;
goto undo;
}
/* Grant foreign access to the page. */
rc = gnttab_grant_foreign_access(op->domid,