thunderbolt: fix memory leak of object sw

In the case where the call tb_switch_exceeds_max_depth is true
the error reurn path leaks memory in sw.  Fix this by setting
the return error code to -EADDRNOTAVAIL and returning via the
error exit path err_free_sw_ports to free sw. sw has been kzalloc'd
so the free of the NULL sw->ports is fine.

Addresses-Coverity: ("Resource leak")
Fixes: b04079837b20 ("thunderbolt: Add initial support for USB4")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191220220526.11307-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 3454e61..ad5479f 100644 (file)
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -1885,8 +1885,10 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
        sw->config.enabled = 0;
 
        /* Make sure we do not exceed maximum topology limit */
-       if (tb_switch_exceeds_max_depth(sw, depth))
-               return ERR_PTR(-EADDRNOTAVAIL);
+       if (tb_switch_exceeds_max_depth(sw, depth)) {
+               ret = -EADDRNOTAVAIL;
+               goto err_free_sw_ports;
+       }
 
        /* initialize ports */
        sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),