From: Mayank Rana mrana@codeaurora.org
commit f247f0a82a4f8c3bfed178d8fd9e069d1424ee4e upstream.
If ucsi_init() fails for some reason (e.g. ucsi_register_port() fails or general communication failure to the PPM), particularly at any point after the GET_CAPABILITY command had been issued, this results in unwinding the initialization and returning an error. However the ucsi structure's ucsi_capability member retains its current value, including likely a non-zero num_connectors. And because ucsi_init() itself is done in a workqueue a UCSI interface driver will be unaware that it failed and may think the ucsi_register() call was completely successful. Later, if ucsi_unregister() is called, due to this stale ucsi->cap value it would try to access the items in the ucsi->connector array which might not be in a proper state or not even allocated at all and results in NULL or invalid pointer dereference.
Fix this by clearing the ucsi->cap value to 0 during the error path of ucsi_init() in order to prevent a later ucsi_unregister() from entering the connector cleanup loop.
Fixes: c1b0bc2dabfa ("usb: typec: Add support for UCSI interface") Cc: stable@vger.kernel.org Acked-by: Heikki Krogerus heikki.krogerus@linux.intel.com Signed-off-by: Mayank Rana mrana@codeaurora.org Signed-off-by: Jack Pham jackp@codeaurora.org Link: https://lore.kernel.org/r/20210609073535.5094-1-jackp@codeaurora.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/typec/ucsi/ucsi.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -724,6 +724,7 @@ err_unregister: }
err_reset: + memset(&ucsi->cap, 0, sizeof(ucsi->cap)); ucsi_reset_ppm(ucsi); err: mutex_unlock(&ucsi->ppm_lock);