From 8bb72ab63d58957270b2dc31e6c9bcfa38470d2c Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 4 Nov 2011 21:24:36 +0300 Subject: [PATCH] xen-gntalloc: signedness bug in add_grefs() commit 99cb2ddcc617f43917e94a4147aa3ccdb2bcd77e upstream. 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. Signed-off-by: Dan Carpenter Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- drivers/xen/gntalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c index 23c60cf4313e..e1c4c6e5b469 100644 --- a/drivers/xen/gntalloc.c +++ b/drivers/xen/gntalloc.c @@ -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; } -- 2.39.5