xhci: Fix memory leak when caching protocol extended capability PSI tables

xhci driver assumed that xHC controllers have at most one custom
supported speed table (PSI) for all usb 3.x ports.
Memory was allocated for one PSI table under the xhci hub structure.

Turns out this is not the case, some controllers have a separate
"supported protocol capability" entry with a PSI table for each port.
This means each usb3 roothub port can in theory support different custom
speeds.

To solve this, cache all supported protocol capabilities with their PSI
tables in an array, and add pointers to the xhci port structure so that
every port points to its capability entry in the array.

When creating the SuperSpeedPlus USB Device Capability BOS descriptor
for the xhci USB 3.1 roothub we for now will use only data from the
first USB 3.1 capable protocol capability entry in the array.
This could be improved later, this patch focuses resolving
the memory leak.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Sajja Venkateswara Rao <VenkateswaraRao.Sajja@amd.com>
Fixes: 47189098f8be ("xhci: parse xhci protocol speed ID list for usb 3.1 usage")
Cc: stable <stable@vger.kernel.org> # v4.4+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200210134553.9144-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 11 insertions, 3 deletions

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 13d8838cd552..3ecee10fdcdc 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1702,12 +1702,20 @@ struct xhci_bus_state {
  * Intel Lynx Point LP xHCI host.
  */
 #define	XHCI_MAX_REXIT_TIMEOUT_MS	20
+struct xhci_port_cap {
+	u32			*psi;	/* array of protocol speed ID entries */
+	u8			psi_count;
+	u8			psi_uid_count;
+	u8			maj_rev;
+	u8			min_rev;
+};
 
 struct xhci_port {
 	__le32 __iomem		*addr;
 	int			hw_portnum;
 	int			hcd_portnum;
 	struct xhci_hub		*rhub;
+	struct xhci_port_cap	*port_cap;
 };
 
 struct xhci_hub {
@@ -1719,9 +1727,6 @@ struct xhci_hub {
 	/* supported prococol extended capabiliy values */
 	u8			maj_rev;
 	u8			min_rev;
-	u32			*psi;	/* array of protocol speed ID entries */
-	u8			psi_count;
-	u8			psi_uid_count;
 };
 
 /* There is one xhci_hcd structure per controller */
@@ -1880,6 +1885,9 @@ struct xhci_hcd {
 	/* cached usb2 extened protocol capabilites */
 	u32                     *ext_caps;
 	unsigned int            num_ext_caps;
+	/* cached extended protocol port capabilities */
+	struct xhci_port_cap	*port_caps;
+	unsigned int		num_port_caps;
 	/* Compliance Mode Recovery Data */
 	struct timer_list	comp_mode_recovery_timer;
 	u32			port_status_u0;