net/mlx4_en: don't set CHECKSUM_COMPLETE on SCTP packets

if the NIC fails to validate the checksum on TCP/UDP, and validation of IP
checksum is successful, the driver subtracts the pseudo-header checksum
from the value obtained by the hardware and sets CHECKSUM_COMPLETE. Don't
do that if protocol is IPPROTO_SCTP, otherwise CRC32c validation fails.

V2: don't test MLX4_CQE_STATUS_IPV6 if MLX4_CQE_STATUS_IPV4 is set

Reported-by: Shuang Li <shuali@redhat.com>
Fixes: f8c6455bb04b ("net/mlx4_en: Extend checksum offloading by CHECKSUM COMPLETE")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 436f768..bf16380 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -574,16 +574,21 @@ static inline __wsum get_fixed_vlan_csum(__wsum hw_checksum,
  * header, the HW adds it. To address that, we are subtracting the pseudo
  * header checksum from the checksum value provided by the HW.
  */
-static void get_fixed_ipv4_csum(__wsum hw_checksum, struct sk_buff *skb,
-                               struct iphdr *iph)
+static int get_fixed_ipv4_csum(__wsum hw_checksum, struct sk_buff *skb,
+                              struct iphdr *iph)
 {
        __u16 length_for_csum = 0;
        __wsum csum_pseudo_header = 0;
+       __u8 ipproto = iph->protocol;
+
+       if (unlikely(ipproto == IPPROTO_SCTP))
+               return -1;
 
        length_for_csum = (be16_to_cpu(iph->tot_len) - (iph->ihl << 2));
        csum_pseudo_header = csum_tcpudp_nofold(iph->saddr, iph->daddr,
-                                               length_for_csum, iph->protocol, 0);
+                                               length_for_csum, ipproto, 0);
        skb->csum = csum_sub(hw_checksum, csum_pseudo_header);
+       return 0;
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -594,17 +599,20 @@ static void get_fixed_ipv4_csum(__wsum hw_checksum, struct sk_buff *skb,
 static int get_fixed_ipv6_csum(__wsum hw_checksum, struct sk_buff *skb,
                               struct ipv6hdr *ipv6h)
 {
+       __u8 nexthdr = ipv6h->nexthdr;
        __wsum csum_pseudo_hdr = 0;
 
-       if (unlikely(ipv6h->nexthdr == IPPROTO_FRAGMENT ||
-                    ipv6h->nexthdr == IPPROTO_HOPOPTS))
+       if (unlikely(nexthdr == IPPROTO_FRAGMENT ||
+                    nexthdr == IPPROTO_HOPOPTS ||
+                    nexthdr == IPPROTO_SCTP))
                return -1;
-       hw_checksum = csum_add(hw_checksum, (__force __wsum)htons(ipv6h->nexthdr));
+       hw_checksum = csum_add(hw_checksum, (__force __wsum)htons(nexthdr));
 
        csum_pseudo_hdr = csum_partial(&ipv6h->saddr,
                                       sizeof(ipv6h->saddr) + sizeof(ipv6h->daddr), 0);
        csum_pseudo_hdr = csum_add(csum_pseudo_hdr, (__force __wsum)ipv6h->payload_len);
-       csum_pseudo_hdr = csum_add(csum_pseudo_hdr, (__force __wsum)ntohs(ipv6h->nexthdr));
+       csum_pseudo_hdr = csum_add(csum_pseudo_hdr,
+                                  (__force __wsum)htons(nexthdr));
 
        skb->csum = csum_sub(hw_checksum, csum_pseudo_hdr);
        skb->csum = csum_add(skb->csum, csum_partial(ipv6h, sizeof(struct ipv6hdr), 0));
@@ -627,11 +635,10 @@ static int check_csum(struct mlx4_cqe *cqe, struct sk_buff *skb, void *va,
        }
 
        if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV4))
-               get_fixed_ipv4_csum(hw_checksum, skb, hdr);
+               return get_fixed_ipv4_csum(hw_checksum, skb, hdr);
 #if IS_ENABLED(CONFIG_IPV6)
-       else if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV6))
-               if (unlikely(get_fixed_ipv6_csum(hw_checksum, skb, hdr)))
-                       return -1;
+       if (cqe->status & cpu_to_be16(MLX4_CQE_STATUS_IPV6))
+               return get_fixed_ipv6_csum(hw_checksum, skb, hdr);
 #endif
        return 0;
 }