xen-gntalloc: signedness bug in add_grefs()

gref->gref_id is unsigned so the error handling didn't work.
gnttab_grant_foreign_access() returns an int type, so we can add a
cast here, and it doesn't cause any problems.
gnttab_grant_foreign_access() can return a variety of errors
including -ENOSPC, -ENOSYS and -ENOMEM.

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Dan Carpenter 2011-11-04 21:24:36 +03:00 committed by Konrad Rzeszutek Wilk
parent 21643e69a4
commit 99cb2ddcc6
1 changed files with 1 additions and 1 deletions

View File

@ -135,7 +135,7 @@ static int add_grefs(struct ioctl_gntalloc_alloc_gref *op,
/* Grant foreign access to the page. */
gref->gref_id = gnttab_grant_foreign_access(op->domid,
pfn_to_mfn(page_to_pfn(gref->page)), readonly);
if (gref->gref_id < 0) {
if ((int)gref->gref_id < 0) {
rc = gref->gref_id;
goto undo;
}