Re: [PATCH v2] sched: check user input value of sysctl_sched_time_avg

[Ethan Zhao]

Peter,


On 2017/9/4 15:49, Peter Zijlstra wrote:

On Sat, Sep 02, 2017 at 02:57:32PM +0800, Ethan Zhao wrote:

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 6648fbb..609bed2 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -367,7 +367,7 @@ static int sysrq_sysctl_handler(struct ctl_table *table, 
int write,
                .data           = &sysctl_sched_time_avg,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = sched_time_avg_handler,

*sigh*, what's wrong with the below? Too easy?

 :),  seems I walked zigzag several cycles to get the right point.

 Thanks,
 Ethan

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 6648fbbb8157..bbbc6a17c15e 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -367,7 +367,8 @@ static struct ctl_table kern_table[] = {
                .data           = &sysctl_sched_time_avg,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = proc_dointvec_min_max,
+               .extra1         = &one,
        },
  #ifdef CONFIG_SCHEDSTATS
        {