RDMA/i40iw: Fix potential use after free

Release variable dst after logging dst->error to avoid possible use after
free.

Link: https://lore.kernel.org/r/1573022651-37171-1-git-send-email-bianpan2016@163.com
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 2d6a378e85609fe0f51f94cb16695b3cba5332b3..bb78d3280accdc7bd54a923db5e9a312217ceb12 100644 (file)
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c
@@ -2079,9 +2079,9 @@ static int i40iw_addr_resolve_neigh_ipv6(struct i40iw_device *iwdev,
        dst = i40iw_get_dst_ipv6(&src_addr, &dst_addr);
        if (!dst || dst->error) {
                if (dst) {
-                       dst_release(dst);
                        i40iw_pr_err("ip6_route_output returned dst->error = %d\n",
                                     dst->error);
+                       dst_release(dst);
                }
                return rc;
        }