From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752898Ab2GWBmQ (ORCPT ); Sun, 22 Jul 2012 21:42:16 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53965 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752860Ab2GWBmM (ORCPT ); Sun, 22 Jul 2012 21:42:12 -0400 Message-Id: <20120723010654.273014446@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 23 Jul 2012 02:07:09 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jason Wang , "Michael S. Tsirkin" Subject: [ 018/108] macvtap: zerocopy: put page when fail to get all requested user pages In-Reply-To: <20120723010651.408577075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wang commit 02ce04bb3d28c3333231f43bca677228dbc686fe upstream. When get_user_pages_fast() fails to get all requested pages, we could not use kfree_skb() to free it as it has not been put in the skb fragments. So we need to call put_page() instead. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin Signed-off-by: Ben Hutchings --- drivers/net/macvtap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 7cb2684..9ab182a 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -531,9 +531,11 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT; num_pages = get_user_pages_fast(base, size, 0, &page[i]); if ((num_pages != size) || - (num_pages > MAX_SKB_FRAGS - skb_shinfo(skb)->nr_frags)) - /* put_page is in skb free */ + (num_pages > MAX_SKB_FRAGS - skb_shinfo(skb)->nr_frags)) { + for (i = 0; i < num_pages; i++) + put_page(page[i]); return -EFAULT; + } truesize = size * PAGE_SIZE; skb->data_len += len; skb->len += len;