From: Jan Beulich jbeulich@suse.com
stable inclusion from linux-4.19.177 commit 717faa776ca2163119239ea58bb78c4d732d8a4f CVE: CVE-2021-26931
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commit 3194a1746e8aabe86075fd3c5e7cf1f4632d7f16 upstream.
In particular -ENOMEM may come back here, from set_foreign_p2m_mapping(). Don't make problems worse, the more that handling elsewhere (together with map's status fields now indicating whether a mapping wasn't even attempted, and hence has to be considered failed) doesn't require this odd way of dealing with errors.
This is part of XSA-362.
Signed-off-by: Jan Beulich jbeulich@suse.com Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross jgross@suse.com Signed-off-by: Juergen Gross jgross@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- drivers/net/xen-netback/netback.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index f228298c3bd0..b29a1b279fff 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1326,13 +1326,11 @@ int xenvif_tx_action(struct xenvif_queue *queue, int budget) return 0;
gnttab_batch_copy(queue->tx_copy_ops, nr_cops); - if (nr_mops != 0) { + if (nr_mops != 0) ret = gnttab_map_refs(queue->tx_map_ops, NULL, queue->pages_to_map, nr_mops); - BUG_ON(ret); - }
work_done = xenvif_tx_submit(queue);