From patchwork Fri Jul 2 06:53:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 12355559 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF00CC11F68 for ; Fri, 2 Jul 2021 06:54:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D768061420 for ; Fri, 2 Jul 2021 06:54:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230135AbhGBG50 (ORCPT ); Fri, 2 Jul 2021 02:57:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:42476 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230093AbhGBG5X (ORCPT ); Fri, 2 Jul 2021 02:57:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 272A961410; Fri, 2 Jul 2021 06:54:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625208891; bh=NFKe+Rh35XCUFQjlTK/C5r/wZ9hR1rSfzhzMNQKZWXk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TvRZop+k2n401pFsbas/CVW3bm74+XhbaKBfce27QrnxiwBF4+7Drowi/O4jEJErk ApD3a5v/fsBnarKjCn4pI/DvcFrEI0iIDAohB9eDGN0fJZ5VdzD6Ze6tpzSEaQDFM5 /SL27l/2bdUy0+z7gd7x/l+UeUxHARI0DAcV1q0s2LJsRdpbD7sBfqYH4nkms5Zyc7 Cu7u1E2tXDPXtJF/+w1JRXQB8aBQWegVDCnNkwgpqkBl7G55KR5X8ah6pQgSbQ08pQ sTwYE4t1vyhoCPvez+Xuz1Oju2i4poy2TCsSajJqP4981fP+IEa8RTfmPf8+uUwOv5 gTb2GBio352OQ== From: Eric Biggers To: linux-fscrypt@vger.kernel.org Cc: linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 2/5] ext4: report correct st_size for encrypted symlinks Date: Thu, 1 Jul 2021 23:53:47 -0700 Message-Id: <20210702065350.209646-3-ebiggers@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210702065350.209646-1-ebiggers@kernel.org> References: <20210702065350.209646-1-ebiggers@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org From: Eric Biggers The stat() family of syscalls report the wrong size for encrypted symlinks, which has caused breakage in several userspace programs. Fix this by calling fscrypt_symlink_getattr() after ext4_getattr() for encrypted symlinks. This function computes the correct size by reading and decrypting the symlink target (if it's not already cached). For more details, see the commit which added fscrypt_symlink_getattr(). Fixes: f348c252320b ("ext4 crypto: add symlink encryption") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers --- fs/ext4/symlink.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index dd05af983092..69109746e6e2 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -52,10 +52,20 @@ static const char *ext4_encrypted_get_link(struct dentry *dentry, return paddr; } +static int ext4_encrypted_symlink_getattr(struct user_namespace *mnt_userns, + const struct path *path, + struct kstat *stat, u32 request_mask, + unsigned int query_flags) +{ + ext4_getattr(mnt_userns, path, stat, request_mask, query_flags); + + return fscrypt_symlink_getattr(path, stat); +} + const struct inode_operations ext4_encrypted_symlink_inode_operations = { .get_link = ext4_encrypted_get_link, .setattr = ext4_setattr, - .getattr = ext4_getattr, + .getattr = ext4_encrypted_symlink_getattr, .listxattr = ext4_listxattr, };