usb: gadget: composite: fix OS descriptors w_value logic
commit ec6ce707 upstream. The OS descriptors logic had the high/low byte of w_value inverted, causing the extended properties to not be accessible for interface != 0. >From the Microsoft documentation: https://learn.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-os-1-0-descriptors-specification OS_Desc_CompatID.doc (w_index = 0x4): - wValue: High Byte = InterfaceNumber. InterfaceNumber is set to the number of the interface or function that is associated with the descriptor, typically 0x00. Because a device can have only one extended compat ID descriptor, it should ignore InterfaceNumber, regardless of the value, and simply return the descriptor. Low Byte = 0. PageNumber is used to retrieve descriptors that are larger than 64 KB. The header section is 16 bytes, so PageNumber is set to 0 for this request. We currently do not support >64KB compat ID descriptors, so verify that the low byte is 0. OS_Desc_Ext_Prop.doc (w_index = 0x5): - wValue: High byte = InterfaceNumber. The high byte of wValue is set to the number of the interface or function that is associated with the descriptor. Low byte = PageNumber. The low byte of wValue is used to retrieve descriptors that are larger than 64 KB. The header section is 10 bytes, so PageNumber is set to 0 for this request. We also don't support >64KB extended properties, so verify that the low byte is 0 and use the high byte for the interface number. Fixes: 37a3a533 ("usb: gadget: OS Feature Descriptors support") Cc: stable <stable@kernel.org> Signed-off-by: Peter Korsgaard <peter@korsgaard.com> Link: https://lore.kernel.org/r/20240404100635.3215340-1-peter@korsgaard.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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