From: Juergen Gross <jgross@suse.com> stable inclusion from linux-4.19.234 commit f85d03f0f482cc28a2ee15a1fed2ae57ae359412 -------------------------------- Commit b0576cc9c6b843d99c6982888d59a56209341888 upstream. Instead of __get_free_pages() and free_pages() use alloc_pages_exact() and free_pages_exact(). This is in preparation of a change of gnttab_end_foreign_access() which will prohibit use of high-order pages. This is part of CVE-2022-23041 / XSA-396. Reported-by: Simon Gaiser <simon@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com> Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> --- drivers/xen/pvcalls-front.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index d7438fdc5706..285bb8390a97 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -346,8 +346,8 @@ static void free_active_ring(struct sock_mapping *map) if (!map->active.ring) return; - free_pages((unsigned long)map->active.data.in, - map->active.ring->ring_order); + free_pages_exact(map->active.data.in, + PAGE_SIZE << map->active.ring->ring_order); free_page((unsigned long)map->active.ring); } @@ -361,8 +361,8 @@ static int alloc_active_ring(struct sock_mapping *map) goto out; map->active.ring->ring_order = PVCALLS_RING_ORDER; - bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - PVCALLS_RING_ORDER); + bytes = alloc_pages_exact(PAGE_SIZE << PVCALLS_RING_ORDER, + GFP_KERNEL | __GFP_ZERO); if (!bytes) goto out; -- 2.22.0