usb: ucsi: Fix NULL pointer deref in ucsi_connector_change()

commit f87fb985452ab2083967103ac00bfd68fb182764 upstream.

When ucsi_init() fails, ucsi->connector is NULL, yet in case of
ucsi_acpi we may still get events which cause the ucs_acpi code to call
ucsi_connector_change(), which then derefs the NULL ucsi->connector
pointer.

Fix this by not setting ucsi->ntfy inside ucsi_init() until ucsi_init()
has succeeded, so that ucsi_connector_change() ignores the events
because UCSI_ENABLE_NTFY_CONNECTOR_CHANGE is not set in the ntfy mask.

Fixes: bdc62f2bae8f ("usb: typec: ucsi: Simplified registration and I/O API")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217106
Cc: stable@vger.kernel.org
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230308154244.722337-2-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 7363958ca1659aa333fc7f756d0f8838e9bee7f5..dca6803a75bddaf725c43a5535751e7154b94c68 100644 (file)
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1202,7 +1202,7 @@ out_unlock:
 static int ucsi_init(struct ucsi *ucsi)
 {
        struct ucsi_connector *con;
-       u64 command;
+       u64 command, ntfy;
        int ret;
        int i;
 
@@ -1214,8 +1214,8 @@ static int ucsi_init(struct ucsi *ucsi)
        }
 
        /* Enable basic notifications */
-       ucsi->ntfy = UCSI_ENABLE_NTFY_CMD_COMPLETE | UCSI_ENABLE_NTFY_ERROR;
-       command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
+       ntfy = UCSI_ENABLE_NTFY_CMD_COMPLETE | UCSI_ENABLE_NTFY_ERROR;
+       command = UCSI_SET_NOTIFICATION_ENABLE | ntfy;
        ret = ucsi_send_command(ucsi, command, NULL, 0);
        if (ret < 0)
                goto err_reset;
@@ -1247,12 +1247,13 @@ static int ucsi_init(struct ucsi *ucsi)
        }
 
        /* Enable all notifications */
-       ucsi->ntfy = UCSI_ENABLE_NTFY_ALL;
-       command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy;
+       ntfy = UCSI_ENABLE_NTFY_ALL;
+       command = UCSI_SET_NOTIFICATION_ENABLE | ntfy;
        ret = ucsi_send_command(ucsi, command, NULL, 0);
        if (ret < 0)
                goto err_unregister;
 
+       ucsi->ntfy = ntfy;
        return 0;
 
 err_unregister: