Revert "UBUNTU: SAUCE: apparmor: fix lock ordering for mkdir"

BugLink: http://bugs.launchpad.net/bugs/1669611
This reverts commit 21c9d3b055706c4b0240e2b9ad88629878e46c83.

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index 290c20ee52c00c68333e8899e5b5d359f23e8056..2ded4188773127ec6a044ba9cf5e88f82c1f068a 100644 (file)
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -1050,7 +1050,6 @@ static int ns_mkdir_op(struct inode *dir, struct dentry *dentry, umode_t mode)
         */
        inode_unlock(dir);
        error = securityfs_pin_fs();
-       mutex_lock(&parent->lock);
        inode_lock_nested(dir, I_MUTEX_PARENT);
        if (error)
                goto out;
@@ -1060,8 +1059,7 @@ static int ns_mkdir_op(struct inode *dir, struct dentry *dentry, umode_t mode)
        if (error)
                goto out_pin;
 
-       ns = __aa_find_or_create_ns(parent, READ_ONCE(dentry->d_name.name),
-                                   dentry);
+       ns = aa_create_ns(parent, ACCESS_ONCE(dentry->d_name.name), dentry);
        if (IS_ERR(ns)) {
                error = PTR_ERR(ns);
                ns = NULL;
@@ -1071,7 +1069,6 @@ static int ns_mkdir_op(struct inode *dir, struct dentry *dentry, umode_t mode)
 out_pin:
        securityfs_release_fs();
 out:
-       mutex_unlock(&parent->lock);
        aa_put_ns(parent);
 
        return error;

diff --git a/security/apparmor/include/policy_ns.h b/security/apparmor/include/policy_ns.h
index 2cf2d3f1295ac71398d94b95fda22d5a82d8af6b..4c16c9acdbcfb78c3e5e910981a577635bcd83a2 100644 (file)
--- a/security/apparmor/include/policy_ns.h
+++ b/security/apparmor/include/policy_ns.h
@@ -88,8 +88,8 @@ void aa_free_ns_kref(struct kref *kref);
 
 struct aa_ns *aa_find_ns(struct aa_ns *root, const char *name);
 struct aa_ns *aa_findn_ns(struct aa_ns *root, const char *name, size_t n);
-struct aa_ns *__aa_find_or_create_ns(struct aa_ns *parent, const char *name,
-                                    struct dentry *dir);
+struct aa_ns *aa_create_ns(struct aa_ns *parent, const char *name,
+                          struct dentry *dir);
 struct aa_ns *aa_prepare_ns(struct aa_ns *root, const char *name);
 void __aa_remove_ns(struct aa_ns *ns);
 

diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c
index 10ccf02d551bae40bc49c98cb3f2073bef38b889..88043fcfad8e55eb9c1841c82c86bbb812f84e45 100644 (file)
--- a/security/apparmor/policy_ns.c
+++ b/security/apparmor/policy_ns.c
@@ -225,13 +225,12 @@ static struct aa_ns *__aa_create_ns(struct aa_ns *parent, const char *name,
  *
  * Returns: the a refcounted ns that has been add or an ERR_PTR
  */
-struct aa_ns *__aa_find_or_create_ns(struct aa_ns *parent, const char *name,
-                                    struct dentry *dir)
+struct aa_ns *aa_create_ns(struct aa_ns *parent, const char *name,
+                          struct dentry *dir)
 {
        struct aa_ns *ns;
 
-       AA_BUG(!mutex_is_locked(&parent->lock));
-
+       mutex_lock(&parent->lock);
        /* try and find the specified ns */
        /* released by caller */
        ns = aa_get_ns(__aa_find_ns(&parent->sub_ns, name));
@@ -239,6 +238,7 @@ struct aa_ns *__aa_find_or_create_ns(struct aa_ns *parent, const char *name,
                ns = __aa_create_ns(parent, name, dir);
        else
                ns = ERR_PTR(-EEXIST);
+       mutex_unlock(&parent->lock);
 
        /* return ref */
        return ns;