| Message ID | 20210609073535.5094-1-jackp@codeaurora.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f247f0a82a4f8c3bfed178d8fd9e069d1424ee4e |
| Headers | show |
| Series | usb: typec: ucsi: Clear PPM capability data in ucsi_init() error path | expand |
On Wed, Jun 09, 2021 at 12:35:35AM -0700, Jack Pham wrote: > From: Mayank Rana <mrana@codeaurora.org> > > 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 > Signed-off-by: Mayank Rana <mrana@codeaurora.org> > Signed-off-by: Jack Pham <jackp@codeaurora.org> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > drivers/usb/typec/ucsi/ucsi.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c > index b433169ef6fa..b7d104c80d85 100644 > --- a/drivers/usb/typec/ucsi/ucsi.c > +++ b/drivers/usb/typec/ucsi/ucsi.c > @@ -1253,6 +1253,7 @@ static int ucsi_init(struct ucsi *ucsi) > } > > err_reset: > + memset(&ucsi->cap, 0, sizeof(ucsi->cap)); > ucsi_reset_ppm(ucsi); > err: > return ret; > -- > 2.24.0
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index b433169ef6fa..b7d104c80d85 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -1253,6 +1253,7 @@ static int ucsi_init(struct ucsi *ucsi) } err_reset: + memset(&ucsi->cap, 0, sizeof(ucsi->cap)); ucsi_reset_ppm(ucsi); err: return ret;