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

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/nes/nes_verbs.c b/drivers/infiniband/hw/nes/nes_verbs.c
index c47ec2599bc9..07e4fbad987a 100644
--- a/drivers/infiniband/hw/nes/nes_verbs.c
+++ b/drivers/infiniband/hw/nes/nes_verbs.c
@@ -2561,6 +2561,11 @@ 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");