Re: [PATCH v3 09/12] usb: misc: lvstest: update to use the usb_control_msg_{send|recv}() API
From: Johan Hovold <johan@kernel.org>
Date: 2021-01-27 15:21:56
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On Wed, Jan 27, 2021 at 12:09:43AM +0530, Anant Thazhemadam wrote:
The newer usb_control_msg_{send|recv}() API are an improvement on the
existing usb_control_msg() as it ensures that a short read/write is treated
as an error, data can be used off the stack, and raw usb pipes need not be
created in the calling functions.
For this reason, instances of usb_control_msg() have been replaced with
usb_control_msg_{recv|send}() and the return value checking conditions have
also been modified appropriately.
Signed-off-by: Anant Thazhemadam <redacted>
---
drivers/usb/misc/lvstest.c | 38 ++++++++++++++++----------------------
1 file changed, 16 insertions(+), 22 deletions(-)quoted hunk ↗ jump to hunk
@@ -336,10 +330,10 @@ static void lvs_rh_work(struct work_struct *work) /* Examine each root port */ for (i = 1; i <= descriptor->bNbrPorts; i++) { - ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), + ret = usb_control_msg_recv(hdev, 0, USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, i, - port_status, sizeof(*port_status), 1000); - if (ret < 4) + port_status, sizeof(*port_status), 1000, GFP_KERNEL); + if (ret < 0) continue;
I'm afraid this may introduce a regression as well since the sizeof(*port_status) is 8 for some devices and the driver only cares about the first 4 that all devices use (i.e. it is written to handle short reads).
quoted hunk ↗ jump to hunk
portchange = le16_to_cpu(port_status->wPortChange);@@ -420,13 +414,13 @@ static int lvs_rh_probe(struct usb_interface *intf, usb_set_intfdata(intf, lvs); /* how many number of ports this root hub has */ - ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), + ret = usb_control_msg_recv(hdev, 0, USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB, USB_DT_SS_HUB << 8, 0, &lvs->descriptor, - USB_DT_SS_HUB_SIZE, USB_CTRL_GET_TIMEOUT); - if (ret < (USB_DT_HUB_NONVAR_SIZE + 2)) { + USB_DT_SS_HUB_SIZE, USB_CTRL_GET_TIMEOUT, GFP_KERNEL); + if (ret < 0) { dev_err(&hdev->dev, "wrong root hub descriptor read %d\n", ret); - return ret < 0 ? ret : -EINVAL; + return ret; }
This looks like it may break for similar reasons. Johan