RDMA/rtrs: Fix some signedness bugs in error handling

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>

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index 468fdd0..96cba06 100644 (file)
--- 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_clt_io_req *req, size_t count)
 
        /* 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;

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
index ba8ab33..eefd149 100644 (file)
--- 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_sess *sess)
                }
                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;
                }