From b73c43f884b1b26ef8e824a33f3924f92e493c11 Mon Sep 17 00:00:00 2001 From: Michał Mirosław Date: Wed, 13 Jul 2011 14:10:29 +0000 Subject: net: sctp: fix checksum marking for outgoing packets MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Packets to devices without NETIF_F_SCTP_CSUM (including NETIF_F_NO_CSUM) should be properly checksummed because the packets can be diverted or rerouted after construction. This still leaves packets diverted from NETIF_F_SCTP_CSUM-enabled devices with broken checksums. Fixing this needs implementing software offload fallback in networking core. For users of sctp_checksum_disable, skb->ip_summed should be left as CHECKSUM_NONE and not CHECKSUM_UNNECESSARY as per include/linux/skbuff.h. Signed-off-by: Michał Mirosław Signed-off-by: David S. Miller --- net/sctp/output.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) (limited to 'net') diff --git a/net/sctp/output.c b/net/sctp/output.c index b4f3cf06d8da..08b3cead6503 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -500,23 +500,20 @@ int sctp_packet_transmit(struct sctp_packet *packet) * Note: Adler-32 is no longer applicable, as has been replaced * by CRC32-C as described in . */ - if (!sctp_checksum_disable && - !(dst->dev->features & (NETIF_F_NO_CSUM | NETIF_F_SCTP_CSUM))) { - __u32 crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len); + if (!sctp_checksum_disable) { + if (!(dst->dev->features & NETIF_F_SCTP_CSUM)) { + __u32 crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len); - /* 3) Put the resultant value into the checksum field in the - * common header, and leave the rest of the bits unchanged. - */ - sh->checksum = sctp_end_cksum(crc32); - } else { - if (dst->dev->features & NETIF_F_SCTP_CSUM) { + /* 3) Put the resultant value into the checksum field in the + * common header, and leave the rest of the bits unchanged. + */ + sh->checksum = sctp_end_cksum(crc32); + } else { /* no need to seed pseudo checksum for SCTP */ nskb->ip_summed = CHECKSUM_PARTIAL; nskb->csum_start = (skb_transport_header(nskb) - nskb->head); nskb->csum_offset = offsetof(struct sctphdr, checksum); - } else { - nskb->ip_summed = CHECKSUM_UNNECESSARY; } } -- cgit v1.2.3