xhci: Fix memory leak when caching protocol extended capability PSI tables - take 2

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>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200211150158.14475-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 37 insertions, 22 deletions

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 0e2701649369..884c601bfa15 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1915,17 +1915,17 @@ no_bw:
 	xhci->usb3_rhub.num_ports = 0;
 	xhci->num_active_eps = 0;
 	kfree(xhci->usb2_rhub.ports);
-	kfree(xhci->usb2_rhub.psi);
 	kfree(xhci->usb3_rhub.ports);
-	kfree(xhci->usb3_rhub.psi);
 	kfree(xhci->hw_ports);
 	kfree(xhci->rh_bw);
 	kfree(xhci->ext_caps);
+	for (i = 0; i < xhci->num_port_caps; i++)
+		kfree(xhci->port_caps[i].psi);
+	kfree(xhci->port_caps);
+	xhci->num_port_caps = 0;
 
 	xhci->usb2_rhub.ports = NULL;
-	xhci->usb2_rhub.psi = NULL;
 	xhci->usb3_rhub.ports = NULL;
-	xhci->usb3_rhub.psi = NULL;
 	xhci->hw_ports = NULL;
 	xhci->rh_bw = NULL;
 	xhci->ext_caps = NULL;
@@ -2126,6 +2126,7 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 	u8 major_revision, minor_revision;
 	struct xhci_hub *rhub;
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
+	struct xhci_port_cap *port_cap;
 
 	temp = readl(addr);
 	major_revision = XHCI_EXT_PORT_MAJOR(temp);
@@ -2160,31 +2161,39 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 		/* WTF? "Valid values are ‘1’ to MaxPorts" */
 		return;
 
-	rhub->psi_count = XHCI_EXT_PORT_PSIC(temp);
-	if (rhub->psi_count) {
-		rhub->psi = kcalloc_node(rhub->psi_count, sizeof(*rhub->psi),
-				    GFP_KERNEL, dev_to_node(dev));
-		if (!rhub->psi)
-			rhub->psi_count = 0;
+	port_cap = &xhci->port_caps[xhci->num_port_caps++];
+	if (xhci->num_port_caps > max_caps)
+		return;
+
+	port_cap->maj_rev = major_revision;
+	port_cap->min_rev = minor_revision;
+	port_cap->psi_count = XHCI_EXT_PORT_PSIC(temp);
+
+	if (port_cap->psi_count) {
+		port_cap->psi = kcalloc_node(port_cap->psi_count,
+					     sizeof(*port_cap->psi),
+					     GFP_KERNEL, dev_to_node(dev));
+		if (!port_cap->psi)
+			port_cap->psi_count = 0;
 
-		rhub->psi_uid_count++;
-		for (i = 0; i < rhub->psi_count; i++) {
-			rhub->psi[i] = readl(addr + 4 + i);
+		port_cap->psi_uid_count++;
+		for (i = 0; i < port_cap->psi_count; i++) {
+			port_cap->psi[i] = readl(addr + 4 + i);
 
 			/* count unique ID values, two consecutive entries can
 			 * have the same ID if link is assymetric
 			 */
-			if (i && (XHCI_EXT_PORT_PSIV(rhub->psi[i]) !=
-				  XHCI_EXT_PORT_PSIV(rhub->psi[i - 1])))
-				rhub->psi_uid_count++;
+			if (i && (XHCI_EXT_PORT_PSIV(port_cap->psi[i]) !=
+				  XHCI_EXT_PORT_PSIV(port_cap->psi[i - 1])))
+				port_cap->psi_uid_count++;
 
 			xhci_dbg(xhci, "PSIV:%d PSIE:%d PLT:%d PFD:%d LP:%d PSIM:%d\n",
-				  XHCI_EXT_PORT_PSIV(rhub->psi[i]),
-				  XHCI_EXT_PORT_PSIE(rhub->psi[i]),
-				  XHCI_EXT_PORT_PLT(rhub->psi[i]),
-				  XHCI_EXT_PORT_PFD(rhub->psi[i]),
-				  XHCI_EXT_PORT_LP(rhub->psi[i]),
-				  XHCI_EXT_PORT_PSIM(rhub->psi[i]));
+				  XHCI_EXT_PORT_PSIV(port_cap->psi[i]),
+				  XHCI_EXT_PORT_PSIE(port_cap->psi[i]),
+				  XHCI_EXT_PORT_PLT(port_cap->psi[i]),
+				  XHCI_EXT_PORT_PFD(port_cap->psi[i]),
+				  XHCI_EXT_PORT_LP(port_cap->psi[i]),
+				  XHCI_EXT_PORT_PSIM(port_cap->psi[i]));
 		}
 	}
 	/* cache usb2 port capabilities */
@@ -2219,6 +2228,7 @@ static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
 			continue;
 		}
 		hw_port->rhub = rhub;
+		hw_port->port_cap = port_cap;
 		rhub->num_ports++;
 	}
 	/* FIXME: Should we disable ports not in the Extended Capabilities? */
@@ -2309,6 +2319,11 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
 	if (!xhci->ext_caps)
 		return -ENOMEM;
 
+	xhci->port_caps = kcalloc_node(cap_count, sizeof(*xhci->port_caps),
+				flags, dev_to_node(dev));
+	if (!xhci->port_caps)
+		return -ENOMEM;
+
 	offset = cap_start;
 
 	while (offset) {