Commit 201c373e authored by Namhyung Kim's avatar Namhyung Kim Committed by Ingo Molnar
Browse files

sched/debug: Limit sd->*_idx range on sysctl 



Various sd->*_idx's are used for refering the rq's load average table
when selecting a cpu to run.  However they can be set to any number
with sysctl knobs so that it can crash the kernel if something bad is
given. Fix it by limiting them into the actual range.

Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1345104204-8317-1-git-send-email-namhyung@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent c751134e

kernel/sched/core.c

+22 −13
Original line number Diff line number Diff line
@@ -4896,16 +4896,25 @@ static void sd_free_ctl_entry(struct ctl_table **tablep) 
	*tablep = NULL;

}



static int min_load_idx = 0;

static int max_load_idx = CPU_LOAD_IDX_MAX;



static void

set_table_entry(struct ctl_table *entry,

		const char *procname, void *data, int maxlen,

		umode_t mode, proc_handler *proc_handler)

		umode_t mode, proc_handler *proc_handler,

		bool load_idx)

{

	entry->procname = procname;

	entry->data = data;

	entry->maxlen = maxlen;

	entry->mode = mode;

	entry->proc_handler = proc_handler;



	if (load_idx) {

		entry->extra1 = &min_load_idx;

		entry->extra2 = &max_load_idx;

	}

}



static struct ctl_table *
@@ -4917,30 +4926,30 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd) 
		return NULL;



	set_table_entry(&table[0], "min_interval", &sd->min_interval,

		sizeof(long), 0644, proc_doulongvec_minmax);

		sizeof(long), 0644, proc_doulongvec_minmax, false);

	set_table_entry(&table[1], "max_interval", &sd->max_interval,

		sizeof(long), 0644, proc_doulongvec_minmax);

		sizeof(long), 0644, proc_doulongvec_minmax, false);

	set_table_entry(&table[2], "busy_idx", &sd->busy_idx,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, true);

	set_table_entry(&table[3], "idle_idx", &sd->idle_idx,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, true);

	set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, true);

	set_table_entry(&table[5], "wake_idx", &sd->wake_idx,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, true);

	set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, true);

	set_table_entry(&table[7], "busy_factor", &sd->busy_factor,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, false);

	set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, false);

	set_table_entry(&table[9], "cache_nice_tries",

		&sd->cache_nice_tries,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, false);

	set_table_entry(&table[10], "flags", &sd->flags,

		sizeof(int), 0644, proc_dointvec_minmax);

		sizeof(int), 0644, proc_dointvec_minmax, false);

	set_table_entry(&table[11], "name", sd->name,

		CORENAME_MAX_SIZE, 0444, proc_dostring);

		CORENAME_MAX_SIZE, 0444, proc_dostring, false);

	/* &table[12] is terminator */



	return table;

CRA Git | Maintained and supported by SUSTech CRA and CCSE