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: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1345104204-8317-1-git-send-email-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Namhyung Kim 2012-08-16 17:03:24 +09:00 committed by Ingo Molnar
parent c751134ef8
commit 201c373e8e

View File

@ -4896,16 +4896,25 @@ static void sd_free_ctl_entry(struct ctl_table **tablep)
*tablep = NULL; *tablep = NULL;
} }
static int min_load_idx = 0;
static int max_load_idx = CPU_LOAD_IDX_MAX;
static void static void
set_table_entry(struct ctl_table *entry, set_table_entry(struct ctl_table *entry,
const char *procname, void *data, int maxlen, 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->procname = procname;
entry->data = data; entry->data = data;
entry->maxlen = maxlen; entry->maxlen = maxlen;
entry->mode = mode; entry->mode = mode;
entry->proc_handler = proc_handler; entry->proc_handler = proc_handler;
if (load_idx) {
entry->extra1 = &min_load_idx;
entry->extra2 = &max_load_idx;
}
} }
static struct ctl_table * static struct ctl_table *
@ -4917,30 +4926,30 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd)
return NULL; return NULL;
set_table_entry(&table[0], "min_interval", &sd->min_interval, 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, 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, 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, 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, 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, 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, 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, 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, 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", set_table_entry(&table[9], "cache_nice_tries",
&sd->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, 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, 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 */ /* &table[12] is terminator */
return table; return table;