@@ -1039,9 +1039,8 @@ static struct fwnode_handle *ucsi_find_fwnode(struct ucsi_connector *con)
return NULL;
}
-static int ucsi_register_port(struct ucsi *ucsi, int index)
+static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
{
- struct ucsi_connector *con = &ucsi->connector[index];
struct typec_capability *cap = &con->typec_cap;
enum typec_accessory *accessory = cap->accessory;
enum usb_role u_role = USB_ROLE_NONE;
@@ -1062,7 +1061,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
init_completion(&con->complete);
mutex_init(&con->lock);
INIT_LIST_HEAD(&con->partner_tasks);
- con->num = index + 1;
con->ucsi = ucsi;
cap->fwnode = ucsi_find_fwnode(con);
@@ -1204,7 +1202,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
*/
static int ucsi_init(struct ucsi *ucsi)
{
- struct ucsi_connector *con;
+ struct ucsi_connector *con, *connector;
u64 command, ntfy;
int ret;
int i;
@@ -1235,16 +1233,16 @@ static int ucsi_init(struct ucsi *ucsi)
}
/* Allocate the connectors. Released in ucsi_unregister() */
- ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
- sizeof(*ucsi->connector), GFP_KERNEL);
- if (!ucsi->connector) {
+ connector = kcalloc(ucsi->cap.num_connectors + 1, sizeof(*connector), GFP_KERNEL);
+ if (!connector) {
ret = -ENOMEM;
goto err_reset;
}
/* Register all connectors */
for (i = 0; i < ucsi->cap.num_connectors; i++) {
- ret = ucsi_register_port(ucsi, i);
+ connector[i].num = i + 1;
+ ret = ucsi_register_port(ucsi, &connector[i]);
if (ret)
goto err_unregister;
}
@@ -1256,11 +1254,12 @@ static int ucsi_init(struct ucsi *ucsi)
if (ret < 0)
goto err_unregister;
+ ucsi->connector = connector;
ucsi->ntfy = ntfy;
return 0;
err_unregister:
- for (con = ucsi->connector; con->port; con++) {
+ for (con = connector; con->port; con++) {
ucsi_unregister_partner(con);
ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
ucsi_unregister_port_psy(con);
@@ -1269,10 +1268,7 @@ static int ucsi_init(struct ucsi *ucsi)
typec_unregister_port(con->port);
con->port = NULL;
}
-
- kfree(ucsi->connector);
- ucsi->connector = NULL;
-
+ kfree(connector);
err_reset:
memset(&ucsi->cap, 0, sizeof(ucsi->cap));
ucsi_reset_ppm(ucsi);
ucsi_init() which runs from a workqueue sets ucsi->connector and on an error will clear it again. ucsi->connector gets dereferenced by ucsi_resume(), this checks for ucsi->connector being NULL in case ucsi_init() has not finished yet; or in case ucsi_init() has failed. ucsi_init() setting ucsi->connector and then clearing it again on an error creates a race where the check in ucsi_resume() may pass, only to have ucsi->connector free-ed underneath it when ucsi_init() hits an error. Fix this race by making ucsi_init() store the connector array in a local variable and only assign it to ucsi->connector on success. Fixes: bdc62f2bae8f ("usb: typec: ucsi: Simplified registration and I/O API") Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- Changes in v3: - Assign connector[i].index before calling ucsi_register_port() instead of passing i to ucsi_register_port() --- drivers/usb/typec/ucsi/ucsi.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-)