lkml.org 
[lkml]   [2008]   [Nov]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] cpuset: rcu_read_lock() to protect task_cs() even we don't dereference to task_cs()'s return value

task_cs() calls cgroup_subsys_state().

we must use rcu_read_lock() to protect cgroup_subsys_state().

in current_cpuset_is_being_rebound(), we don't dereference to task_cs()'s
return value, but task_cs() accesses css_set, this css_set maybe freed
when task_cs() called.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3e00526..e0e087e 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1141,7 +1136,11 @@ done:

int current_cpuset_is_being_rebound(void)
{
- return task_cs(current) == cpuset_being_rebound;
+ struct cpuset *cs;
+ rcu_read_lock();
+ cs = task_cs(current);
+ rcu_read_unlock();
+ return cs == cpuset_being_rebound;
}

static int update_relax_domain_level(struct cpuset *cs, s64 val)


\
 
 \ /
  Last update: 2008-11-21 09:59    [W:0.034 / U:2.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site