diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2018-06-26 16:21:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-04 03:00:50 +0300 |
| commit | 3e3f075f72bd2dfcd5211bd1ff3919bc118ad4cd (patch) | |
| tree | 2ac5423113ef4e8b8039aa4cadf16e69bf8c61a5 /include | |
| parent | a05bd4ba655f5737ead5494733846a87cc80bd36 (diff) | |
| download | linux-3e3f075f72bd2dfcd5211bd1ff3919bc118ad4cd.tar.xz | |
posix-timers: Sanitize overrun handling
[ Upstream commit 78c9c4dfbf8c04883941445a195276bb4bb92c76 ]
The posix timer overrun handling is broken because the forwarding functions
can return a huge number of overruns which does not fit in an int. As a
consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
random number generators.
The k_clock::timer_forward() callbacks return a 64 bit value now. Make
k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
accounting is correct. 3Remove the temporary (int) casts.
Add a helper function which clamps the overrun value returned to user space
via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
between 0 and INT_MAX. INT_MAX is an indicator for user space that the
overrun value has been clamped.
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Link: https://lkml.kernel.org/r/20180626132705.018623573@linutronix.de
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/posix-timers.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h index 672c4f32311e..437a539898ae 100644 --- a/include/linux/posix-timers.h +++ b/include/linux/posix-timers.h @@ -82,8 +82,8 @@ struct k_itimer { clockid_t it_clock; timer_t it_id; int it_active; - int it_overrun; - int it_overrun_last; + s64 it_overrun; + s64 it_overrun_last; int it_requeue_pending; int it_sigev_notify; ktime_t it_interval; |