From: Weitao Hou <houweitaoo@gmail.com>
Date: Thu, 23 May 2019 11:52:08 +0000 (+0800)
Subject: usb: avoid redundant allocation and free of memory
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=086ebf92aa791b6cc8805decffca7b8898d99a4e;p=linux.git

usb: avoid redundant allocation and free of memory

If usb is not attached, it's unnessary to allocate, copy
and free memory

Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index fa783531ee889..aa17dab6c4ea2 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -2130,6 +2130,9 @@ static int proc_ioctl(struct usb_dev_state *ps, struct usbdevfs_ioctl *ctl)
 	if (ps->privileges_dropped)
 		return -EACCES;
 
+	if (!connected(ps))
+		return -ENODEV;
+
 	/* alloc buffer */
 	size = _IOC_SIZE(ctl->ioctl_code);
 	if (size > 0) {
@@ -2146,11 +2149,6 @@ static int proc_ioctl(struct usb_dev_state *ps, struct usbdevfs_ioctl *ctl)
 		}
 	}
 
-	if (!connected(ps)) {
-		kfree(buf);
-		return -ENODEV;
-	}
-
 	if (ps->dev->state != USB_STATE_CONFIGURED)
 		retval = -EHOSTUNREACH;
 	else if (!(intf = usb_ifnum_to_if(ps->dev, ctl->ifno)))