summaryrefslogtreecommitdiff
path: root/net/ipv4/udp.c
diff options
context:
space:
mode:
authorWillem de Bruijn <willemb@google.com>2017-08-10 19:29:19 +0300
committerDavid S. Miller <davem@davemloft.net>2017-08-10 19:52:12 +0300
commit85f1bd9a7b5a79d5baa8bf44af19658f7bf77bfa (patch)
treedcf8a90eb6ae097aa5c962f8bec97e1ce4a5aab7 /net/ipv4/udp.c
parent96d9703050a0036a3360ec98bb41e107c90664fe (diff)
downloadlinux-85f1bd9a7b5a79d5baa8bf44af19658f7bf77bfa.tar.xz
udp: consistently apply ufo or fragmentation
When iteratively building a UDP datagram with MSG_MORE and that datagram exceeds MTU, consistently choose UFO or fragmentation. Once skb_is_gso, always apply ufo. Conversely, once a datagram is split across multiple skbs, do not consider ufo. Sendpage already maintains the first invariant, only add the second. IPv6 does not have a sendpage implementation to modify. A gso skb must have a partial checksum, do not follow sk_no_check_tx in udp_send_skb. Found by syzkaller. Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/udp.c')
-rw-r--r--net/ipv4/udp.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index e6276fa3750b..a7c804f73990 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -802,7 +802,7 @@ static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4)
if (is_udplite) /* UDP-Lite */
csum = udplite_csum(skb);
- else if (sk->sk_no_check_tx) { /* UDP csum disabled */
+ else if (sk->sk_no_check_tx && !skb_is_gso(skb)) { /* UDP csum off */
skb->ip_summed = CHECKSUM_NONE;
goto send;