Commit f3bc432a authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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USB: core: Change %pK for __user pointers to %px 



Commit 2f964780 ("USB: core: replace %p with %pK") used the %pK
format specifier for a bunch of __user pointers.  But as the 'K' in
the specifier indicates, it is meant for kernel pointers.  The reason
for the %pK specifier is to avoid leaks of kernel addresses, but when
the pointer is to an address in userspace the security implications
are minimal.  In particular, no kernel information is leaked.

This patch changes the __user %pK specifiers (used in a bunch of
debugging output lines) to %px, which will always print the actual
address with no mangling.  (Notably, there is no printk format
specifier particularly intended for __user pointers.)

Fixes: 2f964780 ("USB: core: replace %p with %pK")
CC: Vamsi Krishna Samavedam <vskrishn@codeaurora.org>
CC: <stable@vger.kernel.org>
Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20201119170228.GB576844@rowland.harvard.edu


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 184eead0

drivers/usb/core/devio.c

+7 −7
Original line number Diff line number Diff line
@@ -482,11 +482,11 @@ static void snoop_urb(struct usb_device *udev, 


	if (userurb) {		/* Async */

		if (when == SUBMIT)

			dev_info(&udev->dev, "userurb %pK, ep%d %s-%s, "

			dev_info(&udev->dev, "userurb %px, ep%d %s-%s, "

					"length %u\n",

					userurb, ep, t, d, length);

		else

			dev_info(&udev->dev, "userurb %pK, ep%d %s-%s, "

			dev_info(&udev->dev, "userurb %px, ep%d %s-%s, "

					"actual_length %u status %d\n",

					userurb, ep, t, d, length,

					timeout_or_status);
@@ -1997,7 +1997,7 @@ static int proc_reapurb(struct usb_dev_state *ps, void __user *arg) 
	if (as) {

		int retval;



		snoop(&ps->dev->dev, "reap %pK\n", as->userurb);

		snoop(&ps->dev->dev, "reap %px\n", as->userurb);

		retval = processcompl(as, (void __user * __user *)arg);

		free_async(as);

		return retval;
@@ -2014,7 +2014,7 @@ static int proc_reapurbnonblock(struct usb_dev_state *ps, void __user *arg) 


	as = async_getcompleted(ps);

	if (as) {

		snoop(&ps->dev->dev, "reap %pK\n", as->userurb);

		snoop(&ps->dev->dev, "reap %px\n", as->userurb);

		retval = processcompl(as, (void __user * __user *)arg);

		free_async(as);

	} else {
@@ -2142,7 +2142,7 @@ static int proc_reapurb_compat(struct usb_dev_state *ps, void __user *arg) 
	if (as) {

		int retval;



		snoop(&ps->dev->dev, "reap %pK\n", as->userurb);

		snoop(&ps->dev->dev, "reap %px\n", as->userurb);

		retval = processcompl_compat(as, (void __user * __user *)arg);

		free_async(as);

		return retval;
@@ -2159,7 +2159,7 @@ static int proc_reapurbnonblock_compat(struct usb_dev_state *ps, void __user *ar 


	as = async_getcompleted(ps);

	if (as) {

		snoop(&ps->dev->dev, "reap %pK\n", as->userurb);

		snoop(&ps->dev->dev, "reap %px\n", as->userurb);

		retval = processcompl_compat(as, (void __user * __user *)arg);

		free_async(as);

	} else {
@@ -2624,7 +2624,7 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd, 
#endif



	case USBDEVFS_DISCARDURB:

		snoop(&dev->dev, "%s: DISCARDURB %pK\n", __func__, p);

		snoop(&dev->dev, "%s: DISCARDURB %px\n", __func__, p);

		ret = proc_unlinkurb(ps, p);

		break;

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