From ef4b96a5773d7f6568363b3d0c3c3f371fb690bd Mon Sep 17 00:00:00 2001
From: Bob Pearson <rpearsonhpe@gmail.com>
Date: Thu, 29 Jul 2021 17:00:39 -0500
Subject: [PATCH 1/1] RDMA/rxe: Restore setting tot_len in the IPv4 header
Git-commit: ef4b96a5773d7f6568363b3d0c3c3f371fb690bd
Patch-mainline: v5.14
References: git-fixes

An earlier patch removed setting of tot_len in IPv4 headers because it was
also set in ip_local_out. However, this change resulted in an incorrect
ICRC being computed because the tot_len field is not masked out. This
patch restores that line. This fixes the bug reported by Zhu Yanjun.  This
bug affects anyone using rxe which is currently broken.

Fixes: 230bb836ee88 ("RDMA/rxe: Fix redundant call to ip_send_check")
Link: https://lore.kernel.org/r/20210729220039.18549-3-rpearsonhpe@gmail.com
Reported-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Reviewed-and-tested-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
---
 drivers/infiniband/sw/rxe/rxe_net.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
index dec92928a1cd..5ac27f28ace1 100644
--- a/drivers/infiniband/sw/rxe/rxe_net.c
+++ b/drivers/infiniband/sw/rxe/rxe_net.c
@@ -259,6 +259,7 @@ static void prepare_ipv4_hdr(struct dst_entry *dst, struct sk_buff *skb,
 
 	iph->version	=	IPVERSION;
 	iph->ihl	=	sizeof(struct iphdr) >> 2;
+	iph->tot_len	=	htons(skb->len);
 	iph->frag_off	=	df;
 	iph->protocol	=	proto;
 	iph->tos	=	tos;
-- 
2.35.0