Patch "net/mlx4_en: don't set CHECKSUM_COMPLETE on SCTP packets" has been added to the 4.12-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

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

to the 4.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-mlx4_en-don-t-set-checksum_complete-on-sctp-packets.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Fri Aug 11 09:09:38 PDT 2017
From: Davide Caratti <dcaratti@redhat.com>
Date: Thu, 3 Aug 2017 22:54:48 +0200
Subject: net/mlx4_en: don't set CHECKSUM_COMPLETE on SCTP packets

From: Davide Caratti <dcaratti@redhat.com>


[ Upstream commit e718fe450e616227b74d27a233cdf37b4df0c82b ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx4/en_rx.c |   29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -572,16 +572,21 @@ static inline __wsum get_fixed_vlan_csum
  * 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)
@@ -592,17 +597,20 @@ static void get_fixed_ipv4_csum(__wsum h
 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));
@@ -625,11 +633,10 @@ static int check_csum(struct mlx4_cqe *c
 	}
 
 	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;
 }


Patches currently in stable-queue which might be from dcaratti@redhat.com are

queue-4.12/net-mlx4_en-don-t-set-checksum_complete-on-sctp-packets.patch