sctp: Perform software checksum if packet has to be fragmented.

IP/IPv6 fragmentation knows how to compute only TCP/UDP checksum.
This causes problems if SCTP packets has to be fragmented and
ipsummed has been set to PARTIAL due to checksum offload support.
This condition can happen when retransmitting after MTU discover,
or when INIT or other control chunks are larger then MTU.
Check for the rare fragmentation condition in SCTP and use software
checksum calculation in this case.

CC: Fan Du <fan.du@windriver.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vlad Yasevich 2013-10-15 22:01:31 -04:00 committed by David S. Miller
parent 27127a8256
commit d2dbbba77e

View file

@ -537,7 +537,7 @@ int sctp_packet_transmit(struct sctp_packet *packet)
*/
if (!sctp_checksum_disable) {
if (!(dst->dev->features & NETIF_F_SCTP_CSUM) ||
(dst_xfrm(dst) != NULL)) {
(dst_xfrm(dst) != NULL) || packet->ipfragok) {
__u32 crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len);
/* 3) Put the resultant value into the checksum field in the