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)