| Date | Tue, 02 Oct 2012 00:52:18 +0200 | From | Willy Tarreau <> | Subject | [ 021/180] 2.6.32.y: time: Move ktime_t overflow checking into timespec_valid_strict |
| |
2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------
From: John Stultz <john.stultz@linaro.org>
This is a -stable backport of cee58483cf56e0ba355fdd97ff5e8925329aa936
Andreas Bombe reported that the added ktime_t overflow checking added to timespec_valid in commit 4e8b14526ca7 ("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> Cc: Linux Kernel <linux-kernel@vger.kernel.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Willy Tarreau <w@1wt.eu> --- include/linux/time.h | 7 +++++++ kernel/time/timekeeping.c | 6 +++--- 2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/include/linux/time.h b/include/linux/time.h index 146b6f3..bc93987 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -109,6 +109,13 @@ 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; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index b451c93..3d35af3 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -354,7 +354,7 @@ int do_settimeofday(struct timespec *tv) struct timespec ts_delta; unsigned long flags; - if (!timespec_valid(tv)) + if (!timespec_valid_strict(tv)) return -EINVAL; write_seqlock_irqsave(&xtime_lock, flags); @@ -570,7 +570,7 @@ void __init timekeeping_init(void) struct timespec now, boot; read_persistent_clock(&now); - if (!timespec_valid(&now)) { + if (!timespec_valid_strict(&now)) { printk("WARNING: Persistent clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); now.tv_sec = 0; @@ -578,7 +578,7 @@ void __init timekeeping_init(void) } read_boot_clock(&boot); - if (!timespec_valid(&boot)) { + if (!timespec_valid_strict(&boot)) { printk("WARNING: Boot clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); boot.tv_sec = 0; -- 1.7.2.1.45.g54fbc
|