[PATCH 5.10 059/121] net: marvell: prestera: fix double free issue on err path

[Greg Kroah-Hartman]

From: Volodymyr Mytnyk <vmytnyk@xxxxxxxxxxx>

[ Upstream commit e8d032507cb7912baf1d3e0af54516f823befefd ]

fix error path handling in prestera_bridge_port_join() that
cases prestera driver to crash (see below).

 Trace:
   Internal error: Oops: 96000044 [#1] SMP
   Modules linked in: prestera_pci prestera uio_pdrv_genirq
   CPU: 1 PID: 881 Comm: ip Not tainted 5.15.0 #1
   pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
   pc : prestera_bridge_destroy+0x2c/0xb0 [prestera]
   lr : prestera_bridge_port_join+0x2cc/0x350 [prestera]
   sp : ffff800011a1b0f0
   ...
   x2 : ffff000109ca6c80 x1 : dead000000000100 x0 : dead000000000122
    Call trace:
   prestera_bridge_destroy+0x2c/0xb0 [prestera]
   prestera_bridge_port_join+0x2cc/0x350 [prestera]
   prestera_netdev_port_event.constprop.0+0x3c4/0x450 [prestera]
   prestera_netdev_event_handler+0xf4/0x110 [prestera]
   raw_notifier_call_chain+0x54/0x80
   call_netdevice_notifiers_info+0x54/0xa0
   __netdev_upper_dev_link+0x19c/0x380

Fixes: e1189d9a5fbe ("net: marvell: prestera: Add Switchdev driver implementation")
Signed-off-by: Volodymyr Mytnyk <vmytnyk@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/marvell/prestera/prestera_switchdev.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
index 7d83e1f91ef17..9101d00e96b9d 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
@@ -439,8 +439,8 @@ static int prestera_port_bridge_join(struct prestera_port *port,
 
 	br_port = prestera_bridge_port_add(bridge, port->dev);
 	if (IS_ERR(br_port)) {
-		err = PTR_ERR(br_port);
-		goto err_brport_create;
+		prestera_bridge_put(bridge);
+		return PTR_ERR(br_port);
 	}
 
 	if (bridge->vlan_enabled)
@@ -454,8 +454,6 @@ static int prestera_port_bridge_join(struct prestera_port *port,
 
 err_port_join:
 	prestera_bridge_port_put(br_port);
-err_brport_create:
-	prestera_bridge_put(bridge);
 	return err;
 }
 
-- 
2.33.0