| From d472b3a6cf63cd31cae1ed61930f07e6cd6671b5 Mon Sep 17 00:00:00 2001 |
| From: Juergen Gross <jgross@suse.com> |
| Date: Thu, 9 Aug 2018 16:42:16 +0200 |
| Subject: xen/netfront: don't cache skb_shinfo() |
| |
| From: Juergen Gross <jgross@suse.com> |
| |
| commit d472b3a6cf63cd31cae1ed61930f07e6cd6671b5 upstream. |
| |
| skb_shinfo() can change when calling __pskb_pull_tail(): Don't cache |
| its return value. |
| |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Juergen Gross <jgross@suse.com> |
| Reviewed-by: Wei Liu <wei.liu2@citrix.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/net/xen-netfront.c | 8 ++++---- |
| 1 file changed, 4 insertions(+), 4 deletions(-) |
| |
| --- a/drivers/net/xen-netfront.c |
| +++ b/drivers/net/xen-netfront.c |
| @@ -893,7 +893,6 @@ static RING_IDX xennet_fill_frags(struct |
| struct sk_buff *skb, |
| struct sk_buff_head *list) |
| { |
| - struct skb_shared_info *shinfo = skb_shinfo(skb); |
| RING_IDX cons = queue->rx.rsp_cons; |
| struct sk_buff *nskb; |
| |
| @@ -902,15 +901,16 @@ static RING_IDX xennet_fill_frags(struct |
| RING_GET_RESPONSE(&queue->rx, ++cons); |
| skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0]; |
| |
| - if (shinfo->nr_frags == MAX_SKB_FRAGS) { |
| + if (skb_shinfo(skb)->nr_frags == MAX_SKB_FRAGS) { |
| unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to; |
| |
| BUG_ON(pull_to <= skb_headlen(skb)); |
| __pskb_pull_tail(skb, pull_to - skb_headlen(skb)); |
| } |
| - BUG_ON(shinfo->nr_frags >= MAX_SKB_FRAGS); |
| + BUG_ON(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS); |
| |
| - skb_add_rx_frag(skb, shinfo->nr_frags, skb_frag_page(nfrag), |
| + skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, |
| + skb_frag_page(nfrag), |
| rx->offset, rx->status, PAGE_SIZE); |
| |
| skb_shinfo(nskb)->nr_frags = 0; |