From dbdb22754fde671dc93d2fae06f8be113d47f2fb Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 9 May 2014 10:49:03 +0200 Subject: [PATCH] sched: Disallow sched_attr::sched_policy < 0 The scheduler uses policy=-1 to preserve the current policy state to implement sys_sched_setparam(), this got exposed to userspace by accident through sys_sched_setattr(), cure this. Reported-by: Michael Kerrisk Signed-off-by: Peter Zijlstra Acked-by: Michael Kerrisk Cc: Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20140509085311.GJ30445@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index f2205f02eb70..cdefcf7c5925 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3662,6 +3662,9 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, if (retval) return retval; + if (attr.sched_policy < 0) + return -EINVAL; + rcu_read_lock(); retval = -ESRCH; p = find_process_by_pid(pid);