[PATCH 0/3] USB: core: add endpoint-blacklist quirk

[PATCH 0/3] USB: core: add endpoint-blacklist quirk

[Johan Hovold]

This series adds a new endpoint-blacklist device quirk and uses that to
ignore a duplicate endpoint in a broken altsetting of a sound card. The
last patch is just a related cleanup.

Johan


Johan Hovold (3):
  USB: core: add endpoint-blacklist quirk
  USB: quirks: blacklist duplicate ep on Sound Devices USBPre2
  USB: core: clean up endpoint-descriptor parsing

 drivers/usb/core/config.c  | 31 +++++++++++++++++++------------
 drivers/usb/core/quirks.c  | 37 +++++++++++++++++++++++++++++++++++++
 drivers/usb/core/usb.h     |  3 +++
 include/linux/usb/quirks.h |  3 +++
 4 files changed, 62 insertions(+), 12 deletions(-)

-- 
2.24.1

[PATCH 1/3] USB: core: add endpoint-blacklist quirk

[Johan Hovold]

Add a new device quirk that can be used to blacklist endpoints.

Since commit 3e4f8e21c4f2 ("USB: core: fix check for duplicate
endpoints") USB core ignores any duplicate endpoints found during
descriptor parsing.

In order to handle devices where the first interfaces with duplicate
endpoints are the ones that should have their endpoints ignored, we need
to add a blacklist.

Tested-by: edes <edes@gmx.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/core/config.c  | 11 +++++++++++
 drivers/usb/core/quirks.c  | 32 ++++++++++++++++++++++++++++++++
 drivers/usb/core/usb.h     |  3 +++
 include/linux/usb/quirks.h |  3 +++
 4 files changed, 49 insertions(+)

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 26bc05e48d8a..7df22bcefa9d 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -256,6 +256,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 		struct usb_host_interface *ifp, int num_ep,
 		unsigned char *buffer, int size)
 {
+	struct usb_device *udev = to_usb_device(ddev);
 	unsigned char *buffer0 = buffer;
 	struct usb_endpoint_descriptor *d;
 	struct usb_host_endpoint *endpoint;
@@ -297,6 +298,16 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 		goto skip_to_next_endpoint_or_interface_descriptor;
 	}
 
+	/* Ignore blacklisted endpoints */
+	if (udev->quirks & USB_QUIRK_ENDPOINT_BLACKLIST) {
+		if (usb_endpoint_is_blacklisted(udev, ifp, d)) {
+			dev_warn(ddev, "config %d interface %d altsetting %d has a blacklisted endpoint with address 0x%X, skipping\n",
+					cfgno, inum, asnum,
+					d->bEndpointAddress);
+			goto skip_to_next_endpoint_or_interface_descriptor;
+		}
+	}
+
 	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
 	++ifp->desc.bNumEndpoints;
 
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 6b6413073584..56c8dffaf5f5 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -472,6 +472,38 @@ static const struct usb_device_id usb_amd_resume_quirk_list[] = {
 	{ }  /* terminating entry must be last */
 };
 
+/*
+ * Entries for blacklisted endpoints that should be ignored when parsing
+ * configuration descriptors.
+ *
+ * Matched for devices with USB_QUIRK_ENDPOINT_BLACKLIST.
+ */
+static const struct usb_device_id usb_endpoint_blacklist[] = {
+	{ }
+};
+
+bool usb_endpoint_is_blacklisted(struct usb_device *udev,
+		struct usb_host_interface *intf,
+		struct usb_endpoint_descriptor *epd)
+{
+	const struct usb_device_id *id;
+	unsigned int address;
+
+	for (id = usb_endpoint_blacklist; id->match_flags; ++id) {
+		if (!usb_match_device(udev, id))
+			continue;
+
+		if (!usb_match_one_id_intf(udev, intf, id))
+			continue;
+
+		address = id->driver_info;
+		if (address == epd->bEndpointAddress)
+			return true;
+	}
+
+	return false;
+}
+
 static bool usb_match_any_interface(struct usb_device *udev,
 				    const struct usb_device_id *id)
 {
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index cf4783cf661a..3ad0ee57e859 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -37,6 +37,9 @@ extern void usb_authorize_interface(struct usb_interface *);
 extern void usb_detect_quirks(struct usb_device *udev);
 extern void usb_detect_interface_quirks(struct usb_device *udev);
 extern void usb_release_quirk_list(void);
+extern bool usb_endpoint_is_blacklisted(struct usb_device *udev,
+		struct usb_host_interface *intf,
+		struct usb_endpoint_descriptor *epd);
 extern int usb_remove_device(struct usb_device *udev);
 
 extern int usb_get_device_descriptor(struct usb_device *dev,
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index a1be64c9940f..22c1f579afe3 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -69,4 +69,7 @@
 /* Hub needs extra delay after resetting its port. */
 #define USB_QUIRK_HUB_SLOW_RESET		BIT(14)
 
+/* device has blacklisted endpoints */
+#define USB_QUIRK_ENDPOINT_BLACKLIST		BIT(15)
+
 #endif /* __LINUX_USB_QUIRKS_H */
-- 
2.24.1

[PATCH 2/3] USB: quirks: blacklist duplicate ep on Sound Devices USBPre2

[Johan Hovold]

This device has a broken vendor-specific altsetting for interface 1,
where endpoint 0x85 is declared as an isochronous endpoint despite being
used by interface 2 for audio capture.

Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x0926
  idProduct          0x0202
  bcdDevice            1.00
  iManufacturer           1 Sound Devices
  iProduct                2 USBPre2
  iSerial                 3 [...]
  bNumConfigurations      1

[...]

    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       3
      bNumEndpoints           2
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass      0
      bInterfaceProtocol      0
      iInterface              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x85  EP 5 IN
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0126  1x 294 bytes
        bInterval               1

[...]

    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
        bLength                 7
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           4
        bDelay                  1 frames
        wFormatTag         0x0001 PCM
      AudioStreaming Interface Descriptor:
        bLength                26
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bNrChannels             2
        bSubframeSize           2
        bBitResolution         16
        bSamFreqType            6 Discrete
        tSamFreq[ 0]         8000
        tSamFreq[ 1]        16000
        tSamFreq[ 2]        24000
        tSamFreq[ 3]        32000
        tSamFreq[ 4]        44100
        tSamFreq[ 5]        48000
      Endpoint Descriptor:
        bLength                 9
        bDescriptorType         5
        bEndpointAddress     0x85  EP 5 IN
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0126  1x 294 bytes
        bInterval               4
        bRefresh                0
        bSynchAddress           0
        AudioStreaming Endpoint Descriptor:
          bLength                 7
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x01
            Sampling Frequency
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0000

Since commit 3e4f8e21c4f2 ("USB: core: fix check for duplicate
endpoints") USB core ignores any duplicate endpoints found during
descriptor parsing, but in this case we need to ignore the first
instance in order to avoid breaking the audio capture interface.

Fixes: 3e4f8e21c4f2 ("USB: core: fix check for duplicate endpoints")
Cc: stable <stable@vger.kernel.org>
Reported-by: edes <edes@gmx.net>
Tested-by: edes <edes@gmx.net>
Link: https://lore.kernel.org/r/20200201105829.5682c887@acme7.acmenet
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/core/quirks.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 56c8dffaf5f5..f27468966a3d 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -354,6 +354,10 @@ static const struct usb_device_id usb_quirk_list[] = {
 	{ USB_DEVICE(0x0904, 0x6103), .driver_info =
 			USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL },
 
+	/* Sound Devices USBPre2 */
+	{ USB_DEVICE(0x0926, 0x0202), .driver_info =
+			USB_QUIRK_ENDPOINT_BLACKLIST },
+
 	/* Keytouch QWERTY Panel keyboard */
 	{ USB_DEVICE(0x0926, 0x3333), .driver_info =
 			USB_QUIRK_CONFIG_INTF_STRINGS },
@@ -479,6 +483,7 @@ static const struct usb_device_id usb_amd_resume_quirk_list[] = {
  * Matched for devices with USB_QUIRK_ENDPOINT_BLACKLIST.
  */
 static const struct usb_device_id usb_endpoint_blacklist[] = {
+	{ USB_DEVICE_INTERFACE_NUMBER(0x0926, 0x0202, 1), .driver_info = 0x85 },
 	{ }
 };
 
-- 
2.24.1

[PATCH 3/3] USB: core: clean up endpoint-descriptor parsing

[Johan Hovold]

Use the new usb-device pointer instead of back-casting when accessing
the struct usb_device when parsing endpoints.

Note that this introduces two lines that are longer than 80 chars on
purpose.

Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/core/config.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 7df22bcefa9d..b7918f695434 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -322,7 +322,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	j = 255;
 	if (usb_endpoint_xfer_int(d)) {
 		i = 1;
-		switch (to_usb_device(ddev)->speed) {
+		switch (udev->speed) {
 		case USB_SPEED_SUPER_PLUS:
 		case USB_SPEED_SUPER:
 		case USB_SPEED_HIGH:
@@ -343,8 +343,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 			/*
 			 * This quirk fixes bIntervals reported in ms.
 			 */
-			if (to_usb_device(ddev)->quirks &
-				USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
+			if (udev->quirks & USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
 				n = clamp(fls(d->bInterval) + 3, i, j);
 				i = j = n;
 			}
@@ -352,8 +351,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 			 * This quirk fixes bIntervals reported in
 			 * linear microframes.
 			 */
-			if (to_usb_device(ddev)->quirks &
-				USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
+			if (udev->quirks & USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
 				n = clamp(fls(d->bInterval), i, j);
 				i = j = n;
 			}
@@ -370,7 +368,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	} else if (usb_endpoint_xfer_isoc(d)) {
 		i = 1;
 		j = 16;
-		switch (to_usb_device(ddev)->speed) {
+		switch (udev->speed) {
 		case USB_SPEED_HIGH:
 			n = 7;		/* 8 ms = 2^(7-1) uframes */
 			break;
@@ -392,8 +390,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	 * explicitly forbidden by the USB spec.  In an attempt to make
 	 * them usable, we will try treating them as Interrupt endpoints.
 	 */
-	if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
-			usb_endpoint_xfer_bulk(d)) {
+	if (udev->speed == USB_SPEED_LOW && usb_endpoint_xfer_bulk(d)) {
 		dev_warn(ddev, "config %d interface %d altsetting %d "
 		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
 		    cfgno, inum, asnum, d->bEndpointAddress);
@@ -417,7 +414,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 
 	/* Find the highest legal maxpacket size for this endpoint */
 	i = 0;		/* additional transactions per microframe */
-	switch (to_usb_device(ddev)->speed) {
+	switch (udev->speed) {
 	case USB_SPEED_LOW:
 		maxpacket_maxes = low_speed_maxpacket_maxes;
 		break;
@@ -453,8 +450,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	 * maxpacket sizes other than 512.  High speed HCDs may not
 	 * be able to handle that particular bug, so let's warn...
 	 */
-	if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
-			&& usb_endpoint_xfer_bulk(d)) {
+	if (udev->speed == USB_SPEED_HIGH && usb_endpoint_xfer_bulk(d)) {
 		if (maxp != 512)
 			dev_warn(ddev, "config %d interface %d altsetting %d "
 				"bulk endpoint 0x%X has invalid maxpacket %d\n",
@@ -463,7 +459,7 @@ static int usb_parse_endpoint(struct device *ddev, int cfgno,
 	}
 
 	/* Parse a possible SuperSpeed endpoint companion descriptor */
-	if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
+	if (udev->speed >= USB_SPEED_SUPER)
 		usb_parse_ss_endpoint_companion(ddev, cfgno,
 				inum, asnum, endpoint, buffer, size);
 
-- 
2.24.1