diff options
| author | Miaohe Lin <linmiaohe@huawei.com> | 2020-08-15 04:44:31 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-03 11:19:22 +0200 |
| commit | c40fc891ca6c7ada3b10e5c16593e6469d4dfa22 (patch) | |
| tree | 8398d09ecb672726a46c25513f73db0b1769c6a7 | |
| parent | 61b7ab3507b38377aade089bcc2ddd77d7115e72 (diff) | |
net: Fix potential wrong skb->protocol in skb_vlan_untag()
[ Upstream commit 55eff0eb7460c3d50716ed9eccf22257b046ca92 ]
We may access the two bytes after vlan_hdr in vlan_set_encap_proto(). So
we should pull VLAN_HLEN + sizeof(unsigned short) in skb_vlan_untag() or
we may access the wrong data.
Fixes: 0d5501c1c828 ("net: Always untag vlan-tagged traffic on input.")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
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 | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 4e944fe98627..e87ec3659ef6 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -4370,8 +4370,8 @@ struct sk_buff *skb_vlan_untag(struct sk_buff *skb) skb = skb_share_check(skb, GFP_ATOMIC); if (unlikely(!skb)) goto err_free; - - if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) + /* We may access the two bytes after vlan_hdr in vlan_set_encap_proto(). */ + if (unlikely(!pskb_may_pull(skb, VLAN_HLEN + sizeof(unsigned short)))) goto err_free; vhdr = (struct vlan_hdr *)skb->data; |