RDMA/i40iw: Fix potential use after free

[ Upstream commit da046d5f895fca18d63b15ac8faebd5bf784e23a ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 880c63579ba88cb51135ab64a023ad7d3cb8c01e..adec03412506d58bfe6e300e40f7c5d9e58dd377 100644 (file)
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c
@@ -2052,9 +2052,9 @@ 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;
        }