[PATCH 2/2] rxe: correctly calculate iCRC for unaligned payloads

From: Steve Wise <larrystevenwise@gmail.com>
To: linux-rdma@vger.kernel.org
Cc: Steve Wise <larrystevenwise@gmail.com>, bvanassche@acm.org
Subject: [PATCH 2/2] rxe: correctly calculate iCRC for unaligned payloads
Date: Mon,  2 Dec 2019 20:03:20 -0600	[thread overview]
Message-ID: <20191203020319.15036-2-larrystevenwise@gmail.com> (raw)
In-Reply-To: <20191203020319.15036-1-larrystevenwise@gmail.com>

If RoCE PDUs being sent or received contain pad bytes, then the iCRC
is miscalculated resulting PDUs being emitted by RXE with an incorrect
iCRC, as well as ingress PDUs being dropped due to erroneously detecting
a bad iCRC in the PDU.  The fix is to include the pad bytes, if any,
in iCRC computations.

CC: bvanassche@acm.org,3100102071@zju.edu.cn,leon@kernel.org
Signed-off-by: Steve Wise <larrystevenwise@gmail.com>
---
 drivers/infiniband/sw/rxe/rxe_recv.c | 2 +-
 drivers/infiniband/sw/rxe/rxe_req.c  | 6 ++++++
 drivers/infiniband/sw/rxe/rxe_resp.c | 7 +++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c
index f9a492ed900b..831ad578a7b2 100644
--- a/drivers/infiniband/sw/rxe/rxe_recv.c
+++ b/drivers/infiniband/sw/rxe/rxe_recv.c
@@ -389,7 +389,7 @@ void rxe_rcv(struct sk_buff *skb)
 
 	calc_icrc = rxe_icrc_hdr(pkt, skb);
 	calc_icrc = rxe_crc32(rxe, calc_icrc, (u8 *)payload_addr(pkt),
-			      payload_size(pkt));
+			      payload_size(pkt) + bth_pad(pkt));
 	calc_icrc = (__force u32)cpu_to_be32(~calc_icrc);
 	if (unlikely(calc_icrc != pack_icrc)) {
 		if (skb->protocol == htons(ETH_P_IPV6))
diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c
index c5d9b558fa90..e5031172c019 100644
--- a/drivers/infiniband/sw/rxe/rxe_req.c
+++ b/drivers/infiniband/sw/rxe/rxe_req.c
@@ -500,6 +500,12 @@ static int fill_packet(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 			if (err)
 				return err;
 		}
+		if (bth_pad(pkt)) {
+			u8 *pad = payload_addr(pkt) + paylen;
+
+			memset(pad, 0, bth_pad(pkt));
+			crc = rxe_crc32(rxe, crc, pad, bth_pad(pkt));
+		}
 	}
 	p = payload_addr(pkt) + paylen + bth_pad(pkt);
 
diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
index 1cbfbd98eb22..c4a8195bf670 100644
--- a/drivers/infiniband/sw/rxe/rxe_resp.c
+++ b/drivers/infiniband/sw/rxe/rxe_resp.c
@@ -732,6 +732,13 @@ static enum resp_states read_reply(struct rxe_qp *qp,
 	if (err)
 		pr_err("Failed copying memory\n");
 
+	if (bth_pad(&ack_pkt)) {
+		struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
+		u8 *pad = payload_addr(&ack_pkt) + payload;
+
+		memset(pad, 0, bth_pad(&ack_pkt));
+		icrc = rxe_crc32(rxe, icrc, pad, bth_pad(&ack_pkt));
+	}
 	p = payload_addr(&ack_pkt) + payload + bth_pad(&ack_pkt);
 	*p = ~icrc;
 
-- 
2.20.1

