ipmi: Rework SMI registration failure

There were certain situations where ipmi_register_smi() would
return a failure, but the interface would still be registered
and would need to be unregistered.  This is obviously a bad
design and resulted in an oops in certain failure cases.

If the interface is started up in ipmi_register_smi(), then
an error occurs, shut down the interface there so the
cleanup can be done properly.

Fix the various smi users, too.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Reported-by: Justin Ernst <justin.ernst@hpe.com>
Tested-by: Justin Ernst <justin.ernst@hpe.com>
Cc: Andrew Banman <abanman@hpe.com>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: <stable@vger.kernel.org> # 4.18.x

1 files changed, 3 insertions, 10 deletions

diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index 18e4650c233b..c12edc8e91df 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -1214,18 +1214,11 @@ static void shutdown_ssif(void *send_info)
 		complete(&ssif_info->wake_thread);
 		kthread_stop(ssif_info->thread);
 	}
-
-	/*
-	 * No message can be outstanding now, we have removed the
-	 * upper layer and it permitted us to do so.
-	 */
-	kfree(ssif_info);
 }
 
 static int ssif_remove(struct i2c_client *client)
 {
 	struct ssif_info *ssif_info = i2c_get_clientdata(client);
-	struct ipmi_smi *intf;
 	struct ssif_addr_info *addr_info;
 
 	if (!ssif_info)
@@ -1235,9 +1228,7 @@ static int ssif_remove(struct i2c_client *client)
 	 * After this point, we won't deliver anything asychronously
 	 * to the message handler.  We can unregister ourself.
 	 */
-	intf = ssif_info->intf;
-	ssif_info->intf = NULL;
-	ipmi_unregister_smi(intf);
+	ipmi_unregister_smi(ssif_info->intf);
 
 	list_for_each_entry(addr_info, &ssif_infos, link) {
 		if (addr_info->client == client) {
@@ -1246,6 +1237,8 @@ static int ssif_remove(struct i2c_client *client)
 		}
 	}
 
+	kfree(ssif_info);
+
 	return 0;
 }