[PATCH] cgroups: avoid accessing uninitialized data in failure path

Li Zefan
2008-12-23T03:23:21Z

If cgroup_get_rootdir() failed, free_cg_links() will be called
in the failure path, but tmp_cg_links hasn't been initialized
at that time.

I should be blamed to introduce this bug in 2.6.26 merge window.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
kernel/cgroup.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 8185a0f..330b7ae 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1024,7 +1024,7 @@ static int cgroup_get_sb(struct file_system_type *fs_type,
if (ret == -EBUSY) {
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
- goto drop_new_super;
+ goto free_cg_links;
}

/* EBUSY should be the only error here */
@@ -1073,10 +1073,11 @@ static int cgroup_get_sb(struct file_system_type *fs_type,

return simple_set_mnt(mnt, sb);

+ free_cg_links:
+ free_cg_links(&tmp_cg_links);
drop_new_super:
up_write(&sb->s_umount);
deactivate_super(sb);
- free_cg_links(&tmp_cg_links);
return ret;
}

--
1.5.4.rc3