From: Hannes Frederic Sowa Date: Thu, 19 May 2016 13:58:33 +0000 (+0200) Subject: udp: prevent skbs lingering in tunnel socket queues X-Git-Tag: v3.16.42~55 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=df4db51ef4c17ee3bd81eee73b7ee89c14d389ef;p=thirdparty%2Fkernel%2Fstable.git udp: prevent skbs lingering in tunnel socket queues [ Upstream commit e5aed006be918af163eb397e45aa5ea6cefd5e01 ] In case we find a socket with encapsulation enabled we should call the encap_recv function even if just a udp header without payload is available. The callbacks are responsible for correctly verifying and dropping the packets. Also, in case the header validation fails for geneve and vxlan we shouldn't put the skb back into the socket queue, no one will pick them up there. Instead we can simply discard them in the respective encap_recv functions. Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller [bwh: Backported to 3.16: - Drop changes to geneve - vxlan error checking looked a bit different] Signed-off-by: Ben Hutchings --- diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 74dccfa00a5ca..7badf2aa3f61e 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1146,7 +1146,7 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb) /* Need Vxlan and inner Ethernet header to be present */ if (!pskb_may_pull(skb, VXLAN_HLEN)) - goto error; + goto drop; /* Return packets with reserved bits set */ vxh = (struct vxlanhdr *)(udp_hdr(skb) + 1); @@ -1154,7 +1154,7 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb) (vxh->vx_vni & htonl(0xff))) { netdev_dbg(skb->dev, "invalid vxlan flags=%#x vni=%#x\n", ntohl(vxh->vx_flags), ntohl(vxh->vx_vni)); - goto error; + goto drop; } if (iptunnel_pull_header(skb, VXLAN_HLEN, htons(ETH_P_TEB))) @@ -1173,10 +1173,6 @@ drop: /* Consume bad packet */ kfree_skb(skb); return 0; - -error: - /* Return non vxlan pkt */ - return 1; } static void vxlan_rcv(struct vxlan_sock *vs, diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 716475fc884b5..59ddab1fce288 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1533,7 +1533,7 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) /* if we're overly short, let UDP handle it */ encap_rcv = ACCESS_ONCE(up->encap_rcv); - if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) { + if (encap_rcv) { int ret; /* Verify checksum before giving to encap */ diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 8eb38558e157c..067011cff207d 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -631,7 +631,7 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) /* if we're overly short, let UDP handle it */ encap_rcv = ACCESS_ONCE(up->encap_rcv); - if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) { + if (encap_rcv) { int ret; /* Verify checksum before giving to encap */