From 0fdb47440203ce06e09923c4d578cf3c20aef69a Mon Sep 17 00:00:00 2001 From: Pan Bian Date: Mon, 5 Dec 2016 16:23:05 +0800 Subject: [PATCH] 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 Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- drivers/xen/gntalloc.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c index 7a47c4c9fb1b..1bf55a32a4b3 100644 --- a/drivers/xen/gntalloc.c +++ b/drivers/xen/gntalloc.c @@ -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, -- 2.20.1