time: Move ktime_t overflow checking into timespec_valid_strict

Andreas Bombe reported that the added ktime_t overflow checking added to
timespec_valid in commit 4e8b14526c ("time: Improve sanity checking of
timekeeping inputs") was causing problems with X.org because it caused
timeouts larger then KTIME_T to be invalid.

Previously, these large timeouts would be clamped to KTIME_MAX and would
never expire, which is valid.

This patch splits the ktime_t overflow checking into a new
timespec_valid_strict function, and converts the timekeeping codes
internal checking to use this more strict function.

Reported-and-tested-by: Andreas Bombe <aeb@debian.org>
Cc: Zhouping Liu <zliu@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
John Stultz
2012-08-31 13:30:06 -04:00
committed by Linus Torvalds
parent 7a611e69b2
commit cee58483cf
2 changed files with 12 additions and 5 deletions
+7
View File
@@ -125,6 +125,13 @@ static inline bool timespec_valid(const struct timespec *ts)
/* Can't have more nanoseconds then a second */
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return false;
return true;
}
static inline bool timespec_valid_strict(const struct timespec *ts)
{
if (!timespec_valid(ts))
return false;
/* Disallow values that could overflow ktime_t */
if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
return false;