Patch "rxe: correctly calculate iCRC for unaligned payloads" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    rxe: correctly calculate iCRC for unaligned payloads

to the 5.4-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:
     rxe-correctly-calculate-icrc-for-unaligned-payloads.patch
and it can be found in the queue-5.4 subdirectory.

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



commit ecd7705049d0faec686bd67f808efa97abffa8cd
Author: Steve Wise <larrystevenwise@xxxxxxxxx>
Date:   Mon Dec 2 20:03:20 2019 -0600

    rxe: correctly calculate iCRC for unaligned payloads
    
    [ Upstream commit 2030abddec6884aaf5892f5724c48fc340e6826f ]
    
    If RoCE PDUs being sent or received contain pad bytes, then the iCRC
    is miscalculated, resulting in 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.
    
    Note: This bug has caused broken on-the-wire compatibility with actual
    hardware RoCE devices since the soft-RoCE driver was first put into the
    mainstream kernel.  Fixing it will create an incompatibility with the
    original soft-RoCE devices, but is necessary to be compatible with real
    hardware devices.
    
    Fixes: 8700e3e7c485 ("Soft RoCE driver")
    Signed-off-by: Steve Wise <larrystevenwise@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20191203020319.15036-2-larrystevenwise@xxxxxxxxx
    Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

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;