Re: [2/3] gso: Handle new frag_list of frags GRO packets
From: Ben Hutchings <hidden>
Date: 2013-11-07 18:16:49
On Thu, 2013-11-07 at 15:06 +0800, Herbert Xu wrote:
quoted hunk ↗ jump to hunk
Recently GRO started generating packets with frag_lists of frags. This was not handled by GSO, thus leading to a crash. Thankfully these packets are of a regular form and are easy to handle. This patch handles them by calling skb_segment for each frag_list entry. The depth of recursion is limited to just one. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 88b7dc6..bcc3f1c 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c
[...]
quoted hunk ↗ jump to hunk
@@ -2855,8 +2853,40 @@ struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features) nskb->data - tnl_hlen, doffset + tnl_hlen); - if (fskb != skb_shinfo(skb)->frag_list) - goto perform_csum_check; + if (fskb != skb_shinfo(skb)->frag_list) { + struct sk_buff *nsegs; + + if (nskb->len == len + doffset) + goto perform_csum_check; + + SKB_FRAG_ASSERT(nskb); + + __skb_pull(nskb, doffset); + skb_shinfo(nskb)->gso_size = mss; + nsegs = skb_segment(nskb, features); + + err = PTR_ERR(nsegs); + if (IS_ERR(nsegs)) { + kfree(nskb);
Should be kfree_skb().
+ goto err; + } + err = -ENOMEM;
It would be clearer to put this in front of the 'err' label: err_nomem: err = -ENOMEM; and change the allocation failure paths to goto err_nomem.
+ if (segs) + tail->next = nsegs; + else + segs = nsegs; + + tail = nsegs; + while (tail->next) + tail = tail->next; + + BUG_ON(fskb && tail->len != len + doffset);
Deserves a comment, maybe?
+ len = nskb->len;
+ kfree(nskb);
+ continue;
+ }
if (!sg) {
nskb->ip_summed = CHECKSUM_NONE;Ben. -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.