This is a note to let you know that I've just added the patch titled
USB: core: Change %pK for __user pointers to %px
to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From f3bc432aa8a7a2bfe9ebb432502be5c5d979d7fe Mon Sep 17 00:00:00 2001
From: Alan Stern stern@rowland.harvard.edu Date: Thu, 19 Nov 2020 12:02:28 -0500 Subject: USB: core: Change %pK for __user pointers to %px
Commit 2f964780c03b ("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: 2f964780c03b ("USB: core: replace %p with %pK") CC: Vamsi Krishna Samavedam vskrishn@codeaurora.org CC: stable@vger.kernel.org Signed-off-by: Alan Stern stern@rowland.harvard.edu Link: https://lore.kernel.org/r/20201119170228.GB576844@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/core/devio.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index e96a858a1218..533236366a03 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -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;