IB/core: Bound check alternate path port number

The alternate port number is used as an array index in the IB
security implementation, invalid values can result in a kernel panic.

Cc: <stable@vger.kernel.org> # v4.12
Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 16d55710b1162aa11ca2d8ed3dd1c1690f60acc8..d0202bb176a4a6a826b27f2b4327691e334ad4ea 100644 (file)
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1971,6 +1971,12 @@ static int modify_qp(struct ib_uverbs_file *file,
                goto release_qp;
        }
 
+       if ((cmd->base.attr_mask & IB_QP_ALT_PATH) &&
+           !rdma_is_port_valid(qp->device, cmd->base.alt_port_num)) {
+               ret = -EINVAL;
+               goto release_qp;
+       }
+
        attr->qp_state            = cmd->base.qp_state;
        attr->cur_qp_state        = cmd->base.cur_qp_state;
        attr->path_mtu            = cmd->base.path_mtu;