diff options
| author | John Stultz <john.stultz@linaro.org> | 2012-09-11 20:49:53 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-02 09:47:52 -0700 |
| commit | fe979e2c0aa6e5b9157c3b381b43de2ca6965d7e (patch) | |
| tree | c817657cba9d310403f29aeab065fdee3f2be28e | |
| parent | 4ffa9a8069801e36e2aceed5a77482b8b0841757 (diff) | |
time: Move ktime_t overflow checking into timespec_valid_strict
commit cee58483cf56e0ba355fdd97ff5e8925329aa936 upstream
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>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/time.h | 7 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 14 |
2 files changed, 17 insertions, 4 deletions
diff --git a/include/linux/time.h b/include/linux/time.h index c8f723374a7..8c0216e7d30 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -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; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 3bbaf2d068d..c3cbd8c34b4 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -382,7 +382,7 @@ int do_settimeofday(const 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); @@ -428,7 +428,7 @@ int timekeeping_inject_offset(struct timespec *ts) timekeeping_forward_now(); tmp = timespec_add(xtime, *ts); - if (!timespec_valid(&tmp)) { + if (!timespec_valid_strict(&tmp)) { ret = -EINVAL; goto error; } @@ -591,7 +591,7 @@ void __init timekeeping_init(void) struct timespec now, boot; read_persistent_clock(&now); - if (!timespec_valid(&now)) { + if (!timespec_valid_strict(&now)) { pr_warn("WARNING: Persistent clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); now.tv_sec = 0; @@ -599,7 +599,7 @@ void __init timekeeping_init(void) } read_boot_clock(&boot); - if (!timespec_valid(&boot)) { + if (!timespec_valid_strict(&boot)) { pr_warn("WARNING: Boot clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); boot.tv_sec = 0; @@ -649,6 +649,12 @@ static void update_sleep_time(struct timespec t) */ static void __timekeeping_inject_sleeptime(struct timespec *delta) { + if (!timespec_valid_strict(delta)) { + printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " + "sleep delta value!\n"); + return; + } + xtime = timespec_add(xtime, *delta); wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta); update_sleep_time(timespec_add(total_sleep_time, *delta)); |