diff options
author | Michael S. Tsirkin <mst@redhat.com> | 2014-03-10 19:28:08 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-04-14 06:47:19 -0700 |
commit | bb5393acc2ccb3cb0f94cf5f4374ef250b3bca40 (patch) | |
tree | e943e0cb3abcfc77765faf171230093c54d26de9 | |
parent | 0490e20d47bb1b1d26ddcce1d180338560784bf0 (diff) |
skbuff: skb_segment: orphan frags before copying
[ Upstream commit 1fd819ecb90cc9b822cd84d3056ddba315d3340f ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-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 266f178e02ee..9a9898e76c92 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2772,6 +2772,7 @@ 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; @@ -2816,6 +2817,7 @@ 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) { @@ -2903,6 +2905,7 @@ 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); @@ -2917,6 +2920,9 @@ 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); |