diff options
| author | Willem de Bruijn <willemb@google.com> | 2020-01-27 15:40:31 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-01-28 10:56:51 +0100 |
| commit | 6cd021a58c18a1731f7e47f83e172c0c302d65e5 (patch) | |
| tree | 6b69b4a21028a3060fc97ada0491e608e9f73ff8 /include/net | |
| parent | 3127642dc1d16124cdf175f8235e89bc2b63f424 (diff) | |
udp: segment looped gso packets correctly
Multicast and broadcast packets can be looped from egress to ingress
pre segmentation with dev_loopback_xmit. That function unconditionally
sets ip_summed to CHECKSUM_UNNECESSARY.
udp_rcv_segment segments gso packets in the udp rx path. Segmentation
usually executes on egress, and does not expect packets of this type.
__udp_gso_segment interprets !CHECKSUM_PARTIAL as CHECKSUM_NONE. But
the offsets are not correct for gso_make_checksum.
UDP GSO packets are of type CHECKSUM_PARTIAL, with their uh->check set
to the correct pseudo header checksum. Reset ip_summed to this type.
(CHECKSUM_PARTIAL is allowed on ingress, see comments in skbuff.h)
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: cf329aa42b66 ("udp: cope with UDP GRO packet misdirection")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/udp.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/net/udp.h b/include/net/udp.h index 44e0e52b585c..4a180f2a13e3 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -476,6 +476,9 @@ static inline struct sk_buff *udp_rcv_segment(struct sock *sk, if (!inet_get_convert_csum(sk)) features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM; + if (skb->pkt_type == PACKET_LOOPBACK) + skb->ip_summed = CHECKSUM_PARTIAL; + /* the GSO CB lays after the UDP one, no need to save and restore any * CB fragment */ |