From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765716AbdAJNom (ORCPT ); Tue, 10 Jan 2017 08:44:42 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:60578 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765670AbdAJNok (ORCPT ); Tue, 10 Jan 2017 08:44:40 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , Richard Weinberger , Theodore Tso Subject: [PATCH 4.9 008/206] fscrypt: fix renaming and linking special files Date: Tue, 10 Jan 2017 14:34:51 +0100 Message-Id: <20170110131503.135130403@linuxfoundation.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170110131502.767555407@linuxfoundation.org> References: <20170110131502.767555407@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers commit 42d97eb0ade31e1bc537d086842f5d6e766d9d51 upstream. Attempting to link a device node, named pipe, or socket file into an encrypted directory through rename(2) or link(2) always failed with EPERM. This happened because fscrypt_has_permitted_context() saw that the file was unencrypted and forbid creating the link. This behavior was unexpected because such files are never encrypted; only regular files, directories, and symlinks can be encrypted. To fix this, make fscrypt_has_permitted_context() always return true on special files. This will be covered by a test in my encryption xfstests patchset. Fixes: 9bd8212f981e ("ext4 crypto: add encryption policy and password salt support") Signed-off-by: Eric Biggers Reviewed-by: Richard Weinberger Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman --- fs/crypto/policy.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -171,6 +171,11 @@ int fscrypt_has_permitted_context(struct BUG_ON(1); } + /* No restrictions on file types which are never encrypted */ + if (!S_ISREG(child->i_mode) && !S_ISDIR(child->i_mode) && + !S_ISLNK(child->i_mode)) + return 1; + /* no restrictions if the parent directory is not encrypted */ if (!parent->i_sb->s_cop->is_encrypted(parent)) return 1;