From: Oleg Nesterov Date: Fri, 27 Mar 2009 00:06:10 +0000 (+0100) Subject: posix-timers: fix RLIMIT_CPU && setitimer(CPUCLOCK_PROF) X-Git-Tag: v2.6.30-rc2~102^4 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=8f2e586567b1bad72dac7c3810fe9a2ef7117506;p=linux-2.6-block.git posix-timers: fix RLIMIT_CPU && setitimer(CPUCLOCK_PROF) update_rlimit_cpu() tries to optimize out set_process_cpu_timer() in case when we already have CPUCLOCK_PROF timer which should expire first. But it uses cputime_lt() instead of cputime_gt(). Test case: int main(void) { struct itimerval it = { .it_value = { .tv_sec = 1000 }, }; assert(!setitimer(ITIMER_PROF, &it, NULL)); struct rlimit rl = { .rlim_cur = 1, .rlim_max = 1, }; assert(!setrlimit(RLIMIT_CPU, &rl)); for (;;) ; return 0; } Without this patch, the task is not killed as RLIMIT_CPU demands. Signed-off-by: Oleg Nesterov Acked-by: Peter Zijlstra Cc: Peter Lojkin Cc: Roland McGrath Cc: stable@kernel.org LKML-Reference: <20090327000610.GA10108@redhat.com> Signed-off-by: Ingo Molnar --- diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 8e5d9a68b022..bb53185d8c78 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -18,7 +18,7 @@ void update_rlimit_cpu(unsigned long rlim_new) cputime = secs_to_cputime(rlim_new); if (cputime_eq(current->signal->it_prof_expires, cputime_zero) || - cputime_lt(current->signal->it_prof_expires, cputime)) { + cputime_gt(current->signal->it_prof_expires, cputime)) { spin_lock_irq(¤t->sighand->siglock); set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); spin_unlock_irq(¤t->sighand->siglock);