From patchwork Wed Mar 20 18:39:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 10862391 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 70FC41515 for ; Wed, 20 Mar 2019 18:40:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 55C6329C2C for ; Wed, 20 Mar 2019 18:40:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 49C0A29E16; Wed, 20 Mar 2019 18:40:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C773529C2C for ; Wed, 20 Mar 2019 18:40:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727531AbfCTSkR (ORCPT ); Wed, 20 Mar 2019 14:40:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:36608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727307AbfCTSkQ (ORCPT ); Wed, 20 Mar 2019 14:40:16 -0400 Received: from ebiggers-linuxstation.mtv.corp.google.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CD93B21873; Wed, 20 Mar 2019 18:40:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553107215; bh=GVgaWnQRVDs7JRYe6xnoJZc6eiXCKyqXo6bHkLGC1Rk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0Y8/2ajXXylCpL94BCn1e/yyk7Dy9TuPTbDGiY3kRwbwE3ldpc1fNoGMtRj8w/boP S56eq7xpwINi4YBF4SduNyFX1FQNMh0TY9Rlc75/i647zHz/s68hEW2dKCTJcLZZay ULqAZ530hqJSJNLGGnuZOzF01ai2/kfpobmEKHHQ= From: Eric Biggers To: linux-fscrypt@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, linux-unionfs@vger.kernel.org, Sarthak Kukreti , Gao Xiang Subject: [PATCH v2 3/5] fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory Date: Wed, 20 Mar 2019 11:39:11 -0700 Message-Id: <20190320183913.12686-4-ebiggers@kernel.org> X-Mailer: git-send-email 2.21.0.225.g810b269d1ac-goog In-Reply-To: <20190320183913.12686-1-ebiggers@kernel.org> References: <20190320183913.12686-1-ebiggers@kernel.org> MIME-Version: 1.0 Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Eric Biggers Make __d_move() clear DCACHE_ENCRYPTED_NAME on the source dentry. This is needed for when d_splice_alias() moves a directory's encrypted alias to its decrypted alias as a result of the encryption key being added. Otherwise, the decrypted alias will incorrectly be invalidated on the next lookup, causing problems such as unmounting a mount the user just mount()ed there. Note that we don't have to support arbitrary moves of this flag because fscrypt doesn't allow dentries with DCACHE_ENCRYPTED_NAME to be the source or target of a rename(). Fixes: 28b4c263961c ("ext4 crypto: revalidate dentry after adding or removing the key") Reported-by: Sarthak Kukreti Signed-off-by: Eric Biggers --- fs/dcache.c | 2 ++ include/linux/fscrypt.h | 16 ++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/fs/dcache.c b/fs/dcache.c index aac41adf47433..647e6ed426e20 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -2795,6 +2796,7 @@ static void __d_move(struct dentry *dentry, struct dentry *target, list_move(&dentry->d_child, &dentry->d_parent->d_subdirs); __d_rehash(dentry); fsnotify_update_flags(dentry); + fscrypt_handle_d_move(dentry); write_seqcount_end(&target->d_seq); write_seqcount_end(&dentry->d_seq); diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index 4ad7a856e0f1c..39bd2619a3424 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -88,6 +88,18 @@ static inline bool fscrypt_dummy_context_enabled(struct inode *inode) inode->i_sb->s_cop->dummy_context(inode); } +/* + * When d_splice_alias() moves a directory's encrypted alias to its decrypted + * alias as a result of the encryption key being added, DCACHE_ENCRYPTED_NAME + * must be cleared. Note that we don't have to support arbitrary moves of this + * flag because fscrypt doesn't allow encrypted aliases to be the source or + * target of a rename(). + */ +static inline void fscrypt_handle_d_move(struct dentry *dentry) +{ + dentry->d_flags &= ~DCACHE_ENCRYPTED_NAME; +} + /* crypto.c */ extern void fscrypt_enqueue_decrypt_work(struct work_struct *); extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t); @@ -243,6 +255,10 @@ static inline bool fscrypt_dummy_context_enabled(struct inode *inode) return false; } +static inline void fscrypt_handle_d_move(struct dentry *dentry) +{ +} + /* crypto.c */ static inline void fscrypt_enqueue_decrypt_work(struct work_struct *work) {