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author | Peter Korsgaard <peter@korsgaard.com> | 2024-04-04 13:06:35 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-04-24 02:11:48 +0300 |
commit | ec6ce7075ef879b91a8710829016005dc8170f17 (patch) | |
tree | 6f3e4777df8275d76a0b97b8a9f00f35412e88eb /drivers | |
parent | 24729b307eefcd7c476065cd7351c1a018082c19 (diff) | |
download | linux-ec6ce7075ef879b91a8710829016005dc8170f17.tar.xz |
usb: gadget: composite: fix OS descriptors w_value logic
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: 37a3a533429e ("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>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/gadget/composite.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index 0ace45b66a31..0e151b54aae8 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -2112,7 +2112,7 @@ unknown: buf[5] = 0x01; switch (ctrl->bRequestType & USB_RECIP_MASK) { case USB_RECIP_DEVICE: - if (w_index != 0x4 || (w_value >> 8)) + if (w_index != 0x4 || (w_value & 0xff)) break; buf[6] = w_index; /* Number of ext compat interfaces */ @@ -2128,9 +2128,9 @@ unknown: } break; case USB_RECIP_INTERFACE: - if (w_index != 0x5 || (w_value >> 8)) + if (w_index != 0x5 || (w_value & 0xff)) break; - interface = w_value & 0xFF; + interface = w_value >> 8; if (interface >= MAX_CONFIG_INTERFACES || !os_desc_cfg->interface[interface]) break; |