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From: Colin Ian King <colin.king@canonical.com>
Date: Fri, 9 Apr 2021 14:07:26 +0100
Subject: net: thunderx: Fix unintentional sign extension issue
Patch-mainline: v5.13-rc1
Git-commit: e701a25840360706fe4cf5de0015913ca19c274b
References: git-fixes

The shifting of the u8 integers rq->caching by 26 bits to
the left will be promoted to a 32 bit signed int and then
sign-extended to a u64. In the event that rq->caching is
greater than 0x1f then all then all the upper 32 bits of
the u64 end up as also being set because of the int
sign-extension. Fix this by casting the u8 values to a
u64 before the 26 bit left shift.

Addresses-Coverity: ("Unintended sign extension")
Fixes: 4863dea3fab0 ("net: Adding support for Cavium ThunderX network controller")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -779,7 +779,7 @@ static void nicvf_rcv_queue_config(struc
 	mbx.rq.msg = NIC_MBOX_MSG_RQ_CFG;
 	mbx.rq.qs_num = qs->vnic_id;
 	mbx.rq.rq_num = qidx;
-	mbx.rq.cfg = (rq->caching << 26) | (rq->cq_qs << 19) |
+	mbx.rq.cfg = ((u64)rq->caching << 26) | (rq->cq_qs << 19) |
 			  (rq->cq_idx << 16) | (rq->cont_rbdr_qs << 9) |
 			  (rq->cont_qs_rbdr_idx << 8) |
 			  (rq->start_rbdr_qs << 1) | (rq->start_qs_rbdr_idx);