From: Alan Stern stern@rowland.harvard.edu
commit f3bc432aa8a7a2bfe9ebb432502be5c5d979d7fe upstream.
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(-)
--- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -477,11 +477,11 @@ static void snoop_urb(struct usb_device
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); @@ -1945,7 +1945,7 @@ static int proc_reapurb(struct usb_dev_s 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; @@ -1962,7 +1962,7 @@ static int proc_reapurbnonblock(struct u
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 { @@ -2094,7 +2094,7 @@ static int proc_reapurb_compat(struct us 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; @@ -2111,7 +2111,7 @@ static int proc_reapurbnonblock_compat(s
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 { @@ -2540,7 +2540,7 @@ static long usbdev_do_ioctl(struct file #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;