commit 0e334db6bb4b1fd1e2d72c1f3d8f004313cd9f94 breaks timer
From: H.J. Lu
Date: Sun Dec 30 2018 - 21:08:16 EST
On 4.19 branch,
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date: Mon Dec 17 13:31:05 2018 +0100
posix-timers: Fix division by zero bug
commit 0e334db6bb4b1fd1e2d72c1f3d8f004313cd9f94 upstream.
The signal delivery path of posix-timers can try to rearm the timer even if
the interval is zero. That's handled for the common case (hrtimer) but not
for alarm timers. In that case the forwarding function raises a division by
The handling for hrtimer based posix timers is wrong because it marks the
timer as active despite the fact that it is stopped.
Move the check from common_hrtimer_rearm() to posixtimer_rearm() to cure