From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 19 May 2020 16:32:23 +0300
Subject: RDMA/rtrs: Fix some signedness bugs in error handling
Patch-mainline: v5.8-rc1
Git-commit: b386cd65d961e29710ef6ad84bc788f0a7e9d64e
References: jsc#SLE-15176

The problem is that "req->sg_cnt" is an unsigned int so if "nr" is
negative, it gets type promoted to a high positive value and the condition
is false.  This patch fixes it by handling negatives separately.

Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality")
Link: https://lore.kernel.org/r/20200519133223.GN2078@kadam
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/ulp/rtrs/rtrs-clt.c |    7 +++----
 drivers/infiniband/ulp/rtrs/rtrs-srv.c |    2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -1047,11 +1047,10 @@ static int rtrs_map_sg_fr(struct rtrs_cl
 
 	/* Align the MR to a 4K page size to match the block virt boundary */
 	nr = ib_map_mr_sg(req->mr, req->sglist, count, NULL, SZ_4K);
-	if (unlikely(nr < req->sg_cnt)) {
-		if (nr < 0)
-			return nr;
+	if (nr < 0)
+		return nr;
+	if (unlikely(nr < req->sg_cnt))
 		return -EINVAL;
-	}
 	ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey));
 
 	return nr;
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
@@ -649,7 +649,7 @@ static int map_cont_bufs(struct rtrs_srv
 		}
 		nr = ib_map_mr_sg(mr, sgt->sgl, sgt->nents,
 				  NULL, max_chunk_size);
-		if (nr < sgt->nents) {
+		if (nr < 0 || nr < sgt->nents) {
 			err = nr < 0 ? nr : -EINVAL;
 			goto dereg_mr;
 		}