IB/ehca: fix handling idr_alloc result

The function can return negative value.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rdma/ehca/ehca_cq.c b/drivers/staging/rdma/ehca/ehca_cq.c
index 9b68b175069b9a1b6f95bfc1beae065b9ee6b682..ea1b5c1203b4e8292ea6aab4e9760b56c7cbe0b0 100644 (file)
--- a/drivers/staging/rdma/ehca/ehca_cq.c
+++ b/drivers/staging/rdma/ehca/ehca_cq.c
@@ -130,7 +130,7 @@ struct ib_cq *ehca_create_cq(struct ib_device *device,
        void *vpage;
        u32 counter;
        u64 rpage, cqx_fec, h_ret;
-       int ipz_rc, i;
+       int rc, i;
        unsigned long flags;
 
        if (attr->flags)
@@ -170,16 +170,17 @@ struct ib_cq *ehca_create_cq(struct ib_device *device,
 
        idr_preload(GFP_KERNEL);
        write_lock_irqsave(&ehca_cq_idr_lock, flags);
-       my_cq->token = idr_alloc(&ehca_cq_idr, my_cq, 0, 0x2000000, GFP_NOWAIT);
+       rc = idr_alloc(&ehca_cq_idr, my_cq, 0, 0x2000000, GFP_NOWAIT);
        write_unlock_irqrestore(&ehca_cq_idr_lock, flags);
        idr_preload_end();
 
-       if (my_cq->token < 0) {
+       if (rc < 0) {
                cq = ERR_PTR(-ENOMEM);
                ehca_err(device, "Can't allocate new idr entry. device=%p",
                         device);
                goto create_cq_exit1;
        }
+       my_cq->token = rc;
 
        /*
         * CQs maximum depth is 4GB-64, but we need additional 20 as buffer
@@ -195,11 +196,11 @@ struct ib_cq *ehca_create_cq(struct ib_device *device,
                goto create_cq_exit2;
        }
 
-       ipz_rc = ipz_queue_ctor(NULL, &my_cq->ipz_queue, param.act_pages,
+       rc = ipz_queue_ctor(NULL, &my_cq->ipz_queue, param.act_pages,
                                EHCA_PAGESIZE, sizeof(struct ehca_cqe), 0, 0);
-       if (!ipz_rc) {
+       if (!rc) {
                ehca_err(device, "ipz_queue_ctor() failed ipz_rc=%i device=%p",
-                        ipz_rc, device);
+                        rc, device);
                cq = ERR_PTR(-EINVAL);
                goto create_cq_exit3;
        }