USB: Accept bulk endpoints with 1024-byte maxpacket
authorAlan Stern <stern@rowland.harvard.edu>
Thu, 3 May 2018 15:04:48 +0000 (11:04 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 3 May 2018 17:16:38 +0000 (10:16 -0700)
Some non-compliant high-speed USB devices have bulk endpoints with a
1024-byte maxpacket size.  Although such endpoints don't work with
xHCI host controllers, they do work with EHCI controllers.  We used to
accept these invalid sizes (with a warning), but we no longer do
because of an unintentional change introduced by commit aed9d65ac327
("USB: validate wMaxPacketValue entries in endpoint descriptors").

This patch restores the old behavior, so that people with these
peculiar devices can use them without patching their kernels by hand.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Elvinas <elvinas@veikia.lt>
Fixes: aed9d65ac327 ("USB: validate wMaxPacketValue entries in endpoint descriptors")
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/config.c

index c821b4b9647e357468335fca83b3aa980e600315..7b5cb28ffb3578c8785ee4e0ca541c88846890be 100644 (file)
@@ -191,7 +191,9 @@ static const unsigned short full_speed_maxpacket_maxes[4] = {
 static const unsigned short high_speed_maxpacket_maxes[4] = {
        [USB_ENDPOINT_XFER_CONTROL] = 64,
        [USB_ENDPOINT_XFER_ISOC] = 1024,
-       [USB_ENDPOINT_XFER_BULK] = 512,
+
+       /* Bulk should be 512, but some devices use 1024: we will warn below */
+       [USB_ENDPOINT_XFER_BULK] = 1024,
        [USB_ENDPOINT_XFER_INT] = 1024,
 };
 static const unsigned short super_speed_maxpacket_maxes[4] = {