diff options
author | Michael S. Tsirkin <mst@redhat.com> | 2014-03-10 19:28:08 +0200 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2014-07-11 13:34:00 +0100 |
commit | 77c01a54cde87eb3bf6685fb44398352f11db3fa (patch) | |
tree | 6444e61b89e26e82bec2969ea02d34982091f2b3 | |
parent | 3ee479fddc52bbcb3b215be56673e9784890b486 (diff) |
skbuff: skb_segment: orphan frags before copying
commit 1fd819ecb90cc9b822cd84d3056ddba315d3340f upstream.
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>
[bwh: Backported to 3.2. As skb_segment() only supports page-frags *or* a
frag list, there is no need for the additional frag_skb pointer or the
preparatory renaming.]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
-rw-r--r-- | net/core/skbuff.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index e6289b474fe2..7121d9b59bbd 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2698,6 +2698,9 @@ struct sk_buff *skb_segment(struct sk_buff *skb, u32 features) skb_put(nskb, hsize), hsize); while (pos < offset + len && i < nfrags) { + if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) + goto err; + *frag = skb_shinfo(skb)->frags[i]; __skb_frag_ref(frag); size = skb_frag_size(frag); |