| Message ID | 4875a7f58fc31701a14156978dd7d9abe9870908.1560205281.git.sbrivio@redhat.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | Don't assume linear buffers in error handlers for VXLAN and GENEVE | expand |
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 5994d5415a03..4c9bc29fe3d5 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1766,7 +1766,7 @@ static int vxlan_err_lookup(struct sock *sk, struct sk_buff *skb) struct vxlanhdr *hdr; __be32 vni; - if (skb->len < VXLAN_HLEN) + if (!pskb_may_pull(skb, skb_transport_offset(skb) + VXLAN_HLEN)) return -EINVAL; hdr = vxlan_hdr(skb);
In commit c3a43b9fec8a ("vxlan: ICMP error lookup handler") I wrongly assumed buffers from icmp_socket_deliver() would be linear. This is not the case: icmp_socket_deliver() only guarantees we have 8 bytes of linear data. Eric fixed this same issue for fou and fou6 in commits 26fc181e6cac ("fou, fou6: do not assume linear skbs") and 5355ed6388e2 ("fou, fou6: avoid uninit-value in gue_err() and gue6_err()"). Use pskb_may_pull() instead of checking skb->len, and take into account the fact we later access the VXLAN header with udp_hdr(), so we also need to sum skb_transport_header() here. Reported-by: Guillaume Nault <gnault@redhat.com> Fixes: c3a43b9fec8a ("vxlan: ICMP error lookup handler") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> --- drivers/net/vxlan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)