From b94bf594cf8ed67cdd0439e70fa939783471597a Mon Sep 17 00:00:00 2001
From: Myungho Jung <mhjungk@gmail.com>
Date: Wed, 19 Apr 2017 15:24:50 -0700
Subject: [PATCH] timer/sysclt: Restrict timer migration sysctl values to 0 and
1
timer_migration sysctl acts as a boolean switch, so the allowed values
should be restricted to 0 and 1.
Add the necessary extra fields to the sysctl table entry to enforce that.
[ tglx: Rewrote changelog ]
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Link: http://lkml.kernel.org/r/1492640690-3550-1-git-send-email-mhjungk@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
kernel/sysctl.c | 2 ++
kernel/time/timer.c | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index acf0a5a06da7..08637699a862 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1176,6 +1176,8 @@ static struct ctl_table kern_table[] = {
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = timer_migration_handler,
+ .extra1 = &zero,
+ .extra2 = &one,
},
#endif
#ifdef CONFIG_BPF_SYSCALL
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 1dc0256bfb6e..cc6b6bdd1329 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -241,7 +241,7 @@ int timer_migration_handler(struct ctl_table *table, int write,
int ret;
mutex_lock(&mutex);
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (!ret && write)
timers_update_migration(false);
mutex_unlock(&mutex);