diff mbox series

[5.4,141/177] ppdev: fix PPGETTIME/PPSETTIME ioctls

Message ID 20191216174846.834159741@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

gregkh@linuxfoundation.org Dec. 16, 2019, 5:49 p.m. UTC 
From: Arnd Bergmann <arnd@arndb.de>


commit 998174042da229e2cf5841f574aba4a743e69650 upstream.

Going through the uses of timeval in the user space API,
I noticed two bugs in ppdev that were introduced in the y2038
conversion:

* The range check was accidentally moved from ppsettime to
  ppgettime

* On sparc64, the microseconds are in the other half of the
  64-bit word.

Fix both, and mark the fix for stable backports.

Cc: stable@vger.kernel.org
Fixes: 3b9ab374a1e6 ("ppdev: convert to y2038 safe")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Link: https://lore.kernel.org/r/20191108203435.112759-8-arnd@arndb.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


---
 drivers/char/ppdev.c |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)
diff mbox series

Patch

--- a/drivers/char/ppdev.c
+++ b/drivers/char/ppdev.c
@@ -619,20 +619,27 @@  static int pp_do_ioctl(struct file *file
 		if (copy_from_user(time32, argp, sizeof(time32)))
 			return -EFAULT;
 
+		if ((time32[0] < 0) || (time32[1] < 0))
+			return -EINVAL;
+
 		return pp_set_timeout(pp->pdev, time32[0], time32[1]);
 
 	case PPSETTIME64:
 		if (copy_from_user(time64, argp, sizeof(time64)))
 			return -EFAULT;
 
+		if ((time64[0] < 0) || (time64[1] < 0))
+			return -EINVAL;
+
+		if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
+			time64[1] >>= 32;
+
 		return pp_set_timeout(pp->pdev, time64[0], time64[1]);
 
 	case PPGETTIME32:
 		jiffies_to_timespec64(pp->pdev->timeout, &ts);
 		time32[0] = ts.tv_sec;
 		time32[1] = ts.tv_nsec / NSEC_PER_USEC;
-		if ((time32[0] < 0) || (time32[1] < 0))
-			return -EINVAL;
 
 		if (copy_to_user(argp, time32, sizeof(time32)))
 			return -EFAULT;
@@ -643,8 +650,9 @@  static int pp_do_ioctl(struct file *file
 		jiffies_to_timespec64(pp->pdev->timeout, &ts);
 		time64[0] = ts.tv_sec;
 		time64[1] = ts.tv_nsec / NSEC_PER_USEC;
-		if ((time64[0] < 0) || (time64[1] < 0))
-			return -EINVAL;
+
+		if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
+			time64[1] <<= 32;
 
 		if (copy_to_user(argp, time64, sizeof(time64)))
 			return -EFAULT;