From 13d71d7ee644607d525480330c8b6a4268c18c0e Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Wed, 2 May 2012 11:41:58 +0800 Subject: [PATCH 018/109] macvtap: zerocopy: put page when fail to get all requested user pages 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 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index c7a84eb..f217247 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -530,9 +530,11 @@ 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; -- 1.7.7.6