xen: set error code on failures (0fdb4744) · Commits · 戴 / test

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>

drivers/xen/gntalloc.c

+6 −3

Original line number	Diff line number	Diff line
		@@ -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,

Admin message