RDMA/nes: Fix for crash when registering zero length MR for CQ

commit 7d9c199a55200c9b9fcad08e150470d02fb385be upstream.

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/infiniband/hw/nes/nes_verbs.c b/drivers/infiniband/hw/nes/nes_verbs.c
index 5095bc41c6ccdd9203f6259a3a1be294aca9b563..09e83da6d6f5d986e99c9a7e851b3b9749f3454e 100644 (file)
--- a/drivers/infiniband/hw/nes/nes_verbs.c
+++ b/drivers/infiniband/hw/nes/nes_verbs.c
@@ -2559,6 +2559,11 @@ static struct ib_mr *nes_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
                        return ibmr;
                case IWNES_MEMREG_TYPE_QP:
                case IWNES_MEMREG_TYPE_CQ:
+                       if (!region->length) {
+                               nes_debug(NES_DBG_MR, "Unable to register zero length region for CQ\n");
+                               ib_umem_release(region);
+                               return ERR_PTR(-EINVAL);
+                       }
                        nespbl = kzalloc(sizeof(*nespbl), GFP_KERNEL);
                        if (!nespbl) {
                                nes_debug(NES_DBG_MR, "Unable to allocate PBL\n");