@@ -2468,8 +2468,16 @@ void cpuset_print_task_mems_allowed(struct task_struct *tsk)
dentry = task_cs(tsk)->css.cgroup->dentry;
spin_lock(&cpuset_buffer_lock);
- snprintf(cpuset_name, CPUSET_NAME_LEN,
- dentry ? (const char *)dentry->d_name.name : "/");
+
+ if (!dentry) {
+ strcpy(cpuset_name, "/");
+ } else {
+ spin_lock(&dentry->d_lock);
+ strlcpy(cpuset_name, (const char *)dentry->d_name.name,
+ CPUSET_NAME_LEN);
+ spin_unlock(&dentry->d_lock);
+ }
+
nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN,
tsk->mems_allowed);
printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n",
This is a note to let you know that I have just added a patch titled cpuset: fix cpuset_print_task_mems_allowed() vs rename() race to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From e0e23a088e2a502e128a030f610c1d2b60a868f9 Mon Sep 17 00:00:00 2001 From: Li Zefan <lizefan@huawei.com> Date: Fri, 25 Jan 2013 16:08:01 +0800 Subject: [PATCH] cpuset: fix cpuset_print_task_mems_allowed() vs rename() race commit 63f43f55c9bbc14f76b582644019b8a07dc8219a upstream. rename() will change dentry->d_name. The result of this race can be worse than seeing partially rewritten name, but we might access a stale pointer because rename() will re-allocate memory to hold a longer name. It's safe in the protection of dentry->d_lock. v2: check NULL dentry before acquiring dentry lock. Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- kernel/cpuset.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) -- 1.8.1.2