diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2014-03-10 19:28:08 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-03-11 16:26:38 -0400 |
| commit | 1fd819ecb90cc9b822cd84d3056ddba315d3340f (patch) | |
| tree | a6ebab17f5c69d2c9ef08aa5fa1426201adfa7e7 | |
| parent | 1a4cedaf65491e66e1e55b8428c89209da729209 (diff) | |
skbuff: skb_segment: orphan frags before copying
skb_segment copies frags around, so we need
to copy them carefully to avoid accessing
user memory after reporting completion to userspace
through a callback.
skb_segment doesn't normally happen on datapath:
TSO needs to be disabled - so disabling zero copy
in this case does not look like a big deal.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/skbuff.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index dc4f7683ff52..869c7afe3b07 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2854,6 +2854,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, skb_frag_t *frag = skb_shinfo(head_skb)->frags; unsigned int mss = skb_shinfo(head_skb)->gso_size; unsigned int doffset = head_skb->data - skb_mac_header(head_skb); + struct sk_buff *frag_skb = head_skb; unsigned int offset = doffset; unsigned int tnl_hlen = skb_tnl_header_len(head_skb); unsigned int headroom; @@ -2898,6 +2899,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, i = 0; nfrags = skb_shinfo(list_skb)->nr_frags; frag = skb_shinfo(list_skb)->frags; + frag_skb = list_skb; pos += skb_headlen(list_skb); while (pos < offset + len) { @@ -2985,6 +2987,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, i = 0; nfrags = skb_shinfo(list_skb)->nr_frags; frag = skb_shinfo(list_skb)->frags; + frag_skb = list_skb; BUG_ON(!nfrags); @@ -2999,6 +3002,9 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, goto err; } + if (unlikely(skb_orphan_frags(frag_skb, GFP_ATOMIC))) + goto err; + *nskb_frag = *frag; __skb_frag_ref(nskb_frag); size = skb_frag_size(nskb_frag); |