diff options
| author |   Daniel Borkmann <daniel@iogearbox.net> | 2016-04-16 02:27:58 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2016-04-15 23:20:11 -0400 |
| commit | 9241e2df4fbc648a92ea0752918e05c26255649e (patch) | |
| tree | a4140463f6cdb8ac8471238b1dc59130258f559d /net/core/skbuff.c | |
| parent | cpsw: Prevent NUll pointer dereference with two PHYs (diff) | |
| download | linux-dev-9241e2df4fbc648a92ea0752918e05c26255649e.tar.xz linux-dev-9241e2df4fbc648a92ea0752918e05c26255649e.zip | |
vlan: pull on __vlan_insert_tag error path and fix csum correction
When __vlan_insert_tag() fails from skb_vlan_push() path due to the
skb_cow_head(), we need to undo the __skb_push() in the error path
as well that was done earlier to move skb->data pointer to mac header.
Moreover, I noticed that when in the non-error path the __skb_pull()
is done and the original offset to mac header was non-zero, we fixup
from a wrong skb->data offset in the checksum complete processing.
So the skb_postpush_rcsum() really needs to be done before __skb_pull()
where skb->data still points to the mac header start and thus operates
under the same conditions as in __vlan_insert_tag().
Fixes: 93515d53b133 ("net: move vlan pop/push functions into common code")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/skbuff.c')
| -rw-r--r-- | net/core/skbuff.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d04c2d1c8c87..e561f9f07d6d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -4502,13 +4502,16 @@ int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) __skb_push(skb, offset); err = __vlan_insert_tag(skb, skb->vlan_proto, skb_vlan_tag_get(skb)); - if (err) + if (err) { + __skb_pull(skb, offset); return err; + } + skb->protocol = skb->vlan_proto; skb->mac_len += VLAN_HLEN; - __skb_pull(skb, offset); skb_postpush_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN); + __skb_pull(skb, offset); } __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); return 0; |