Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro:

 - a couple of ->i_link use-after-free fixes

 - regression fix for wrong errno on absent device name in mount(2)
   (this cycle stuff)

 - ancient UFS braino in large GID handling on Solaris UFS images (bogus
   cut'n'paste from large UID handling; wrong field checked to decide
   whether we should look at old (16bit) or new (32bit) field)

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour
  Abort file_remove_privs() for non-reg. files
  [fix] get rid of checking for absent device name in vfs_get_tree()
  apparmorfs: fix use-after-free on symlink traversal
  securityfs: fix use-after-free on symlink traversal

5 files changed, 26 insertions, 16 deletions

diff --git a/fs/inode.c b/fs/inode.c
index e9d97add2b36..9a453f3637f8 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1817,8 +1817,13 @@ int file_remove_privs(struct file *file)
         int kill;
         int error = 0;
 
-        /* Fast path for nothing security related */
-        if (IS_NOSEC(inode))
+        /*
+         * Fast path for nothing security related.
+         * As well for non-regular files, e.g. blkdev inodes.
+         * For example, blkdev_write_iter() might get here
+         * trying to remove privs which it is not allowed to.
+         */
+        if (IS_NOSEC(inode) || !S_ISREG(inode->i_mode))
                 return 0;
 
         kill = dentry_needs_remove_privs(dentry);
diff --git a/fs/super.c b/fs/super.c
index 583a0124bc39..2739f57515f8 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1467,11 +1467,6 @@ int vfs_get_tree(struct fs_context *fc)
         struct super_block *sb;
         int error;
 
-        if (fc->fs_type->fs_flags & FS_REQUIRES_DEV && !fc->source) {
-                errorf(fc, "Filesystem requires source device");
-                return -ENOENT;
-        }
-
         if (fc->root)
                 return -EBUSY;
 
diff --git a/fs/ufs/util.h b/fs/ufs/util.h
index 1fd3011ea623..7fd4802222b8 100644
--- a/fs/ufs/util.h
+++ b/fs/ufs/util.h
@@ -229,7 +229,7 @@ ufs_get_inode_gid(struct super_block *sb, struct ufs_inode *inode)
         case UFS_UID_44BSD:
                 return fs32_to_cpu(sb, inode->ui_u3.ui_44.ui_gid);
         case UFS_UID_EFT:
-                if (inode->ui_u1.oldids.ui_suid == 0xFFFF)
+                if (inode->ui_u1.oldids.ui_sgid == 0xFFFF)
                         return fs32_to_cpu(sb, inode->ui_u3.ui_sun.ui_gid);
                 /* Fall through */
         default:
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index fefee040bf79..b9298d2e8165 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -123,17 +123,22 @@ static int aafs_show_path(struct seq_file *seq, struct dentry *dentry)
         return 0;
 }
 
-static void aafs_evict_inode(struct inode *inode)
+static void aafs_i_callback(struct rcu_head *head)
 {
-        truncate_inode_pages_final(&inode->i_data);
-        clear_inode(inode);
+        struct inode *inode = container_of(head, struct inode, i_rcu);
         if (S_ISLNK(inode->i_mode))
                 kfree(inode->i_link);
+        free_inode_nonrcu(inode);
+}
+
+static void aafs_destroy_inode(struct inode *inode)
+{
+        call_rcu(&inode->i_rcu, aafs_i_callback);
 }
 
 static const struct super_operations aafs_super_ops = {
         .statfs = simple_statfs,
-        .evict_inode = aafs_evict_inode,
+        .destroy_inode = aafs_destroy_inode,
         .show_path = aafs_show_path,
 };
 
diff --git a/security/inode.c b/security/inode.c
index b7772a9b315e..421dd72b5876 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -27,17 +27,22 @@
 static struct vfsmount *mount;
 static int mount_count;
 
-static void securityfs_evict_inode(struct inode *inode)
+static void securityfs_i_callback(struct rcu_head *head)
 {
-        truncate_inode_pages_final(&inode->i_data);
-        clear_inode(inode);
+        struct inode *inode = container_of(head, struct inode, i_rcu);
         if (S_ISLNK(inode->i_mode))
                 kfree(inode->i_link);
+        free_inode_nonrcu(inode);
+}
+
+static void securityfs_destroy_inode(struct inode *inode)
+{
+        call_rcu(&inode->i_rcu, securityfs_i_callback);
 }
 
 static const struct super_operations securityfs_super_operations = {
         .statfs         = simple_statfs,
-        .evict_inode    = securityfs_evict_inode,
+        .destroy_inode  = securityfs_destroy_inode,
 };
 
 static int fill_super(struct super_block *sb, void *data, int silent)