diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2023-08-04 15:12:21 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-08 10:45:32 +0200 |
| commit | de28e469da75359a2bb8cd8778b78aa64b1be1f4 (patch) | |
| tree | 7bb3ea32ca3bb69414eb43633ec50529b347f087 /drivers/usb/core/hcd.c | |
| parent | 85d07c55621676d47d873d2749b88f783cd4d5a1 (diff) | |
USB: core: Change usb_get_device_descriptor() API
The usb_get_device_descriptor() routine reads the device descriptor
from the udev device and stores it directly in udev->descriptor. This
interface is error prone, because the USB subsystem expects in-memory
copies of a device's descriptors to be immutable once the device has
been initialized.
The interface is changed so that the device descriptor is left in a
kmalloc-ed buffer, not copied into the usb_device structure. A
pointer to the buffer is returned to the caller, who is then
responsible for kfree-ing it. The corresponding changes needed in the
various callers are fairly small.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/d0111bb6-56c1-4f90-adf2-6cfe152f6561@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/core/hcd.c')
| -rw-r--r-- | drivers/usb/core/hcd.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 8300baedafd2..6af0a31ff147 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -983,6 +983,7 @@ static int register_root_hub(struct usb_hcd *hcd) { struct device *parent_dev = hcd->self.controller; struct usb_device *usb_dev = hcd->self.root_hub; + struct usb_device_descriptor *descr; const int devnum = 1; int retval; @@ -994,13 +995,16 @@ static int register_root_hub(struct usb_hcd *hcd) mutex_lock(&usb_bus_idr_lock); usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); - retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE); - if (retval != sizeof usb_dev->descriptor) { + descr = usb_get_device_descriptor(usb_dev); + if (IS_ERR(descr)) { + retval = PTR_ERR(descr); mutex_unlock(&usb_bus_idr_lock); dev_dbg (parent_dev, "can't read %s device descriptor %d\n", dev_name(&usb_dev->dev), retval); - return (retval < 0) ? retval : -EMSGSIZE; + return retval; } + usb_dev->descriptor = *descr; + kfree(descr); if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) { retval = usb_get_bos_descriptor(usb_dev); |