From patchwork Tue May 5 05:21:36 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 6334441 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 89314BEEE1 for ; Tue, 5 May 2015 05:28:45 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9708520117 for ; Tue, 5 May 2015 05:28:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B3EF20266 for ; Tue, 5 May 2015 05:28:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755894AbbEEF2d (ORCPT ); Tue, 5 May 2015 01:28:33 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:40095 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755694AbbEEFXX (ORCPT ); Tue, 5 May 2015 01:23:23 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.76 #1 (Red Hat Linux)) id 1YpVJl-0001II-Ja; Tue, 05 May 2015 05:22:53 +0000 From: Al Viro To: Linus Torvalds Cc: Neil Brown , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 02/79] 9p: don't bother with __getname() in ->follow_link() Date: Tue, 5 May 2015 06:21:36 +0100 Message-Id: <1430803373-4948-2-git-send-email-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <20150505052205.GS889@ZenIV.linux.org.uk> References: <20150505052205.GS889@ZenIV.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Al Viro We copy there a kmalloc'ed string and proceed to kfree that string immediately after that. Easier to just feed that string to nd_set_link() and _not_ kfree it until ->put_link() (which becomes kfree_put_link() in that case). Signed-off-by: Al Viro --- fs/9p/v9fs.h | 2 -- fs/9p/vfs_inode.c | 93 ++++++++++---------------------------------------- fs/9p/vfs_inode_dotl.c | 31 +++++------------ 3 files changed, 26 insertions(+), 100 deletions(-) diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h index fb9ffcb..0923f2c 100644 --- a/fs/9p/v9fs.h +++ b/fs/9p/v9fs.h @@ -149,8 +149,6 @@ extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d); extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d); extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry); -extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, - void *p); extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, struct super_block *sb, int new); diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index cda68f7..0ba1171 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -1224,103 +1224,46 @@ ino_t v9fs_qid2ino(struct p9_qid *qid) } /** - * v9fs_readlink - read a symlink's location (internal version) + * v9fs_vfs_follow_link - follow a symlink path * @dentry: dentry for symlink - * @buffer: buffer to load symlink location into - * @buflen: length of buffer + * @nd: nameidata * */ -static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) +static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) { - int retval; - - struct v9fs_session_info *v9ses; - struct p9_fid *fid; + struct v9fs_session_info *v9ses = v9fs_dentry2v9ses(dentry); + struct p9_fid *fid = v9fs_fid_lookup(dentry); struct p9_wstat *st; - p9_debug(P9_DEBUG_VFS, " %pd\n", dentry); - retval = -EPERM; - v9ses = v9fs_dentry2v9ses(dentry); - fid = v9fs_fid_lookup(dentry); + p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); + if (IS_ERR(fid)) - return PTR_ERR(fid); + return ERR_CAST(fid); if (!v9fs_proto_dotu(v9ses)) - return -EBADF; + return ERR_PTR(-EBADF); st = p9_client_stat(fid); if (IS_ERR(st)) - return PTR_ERR(st); + return ERR_CAST(st); if (!(st->mode & P9_DMSYMLINK)) { - retval = -EINVAL; - goto done; + p9stat_free(st); + kfree(st); + return ERR_PTR(-EINVAL); } + if (strlen(st->extension) >= PATH_MAX) + st->extension[PATH_MAX - 1] = '\0'; - /* copy extension buffer into buffer */ - retval = min(strlen(st->extension)+1, (size_t)buflen); - memcpy(buffer, st->extension, retval); - - p9_debug(P9_DEBUG_VFS, "%pd -> %s (%.*s)\n", - dentry, st->extension, buflen, buffer); - -done: + nd_set_link(nd, st->extension); + st->extension = NULL; p9stat_free(st); kfree(st); - return retval; -} - -/** - * v9fs_vfs_follow_link - follow a symlink path - * @dentry: dentry for symlink - * @nd: nameidata - * - */ - -static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) -{ - int len = 0; - char *link = __getname(); - - p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); - - if (!link) - link = ERR_PTR(-ENOMEM); - else { - len = v9fs_readlink(dentry, link, PATH_MAX); - - if (len < 0) { - __putname(link); - link = ERR_PTR(len); - } else - link[min(len, PATH_MAX-1)] = 0; - } - nd_set_link(nd, link); - return NULL; } /** - * v9fs_vfs_put_link - release a symlink path - * @dentry: dentry for symlink - * @nd: nameidata - * @p: unused - * - */ - -void -v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p) -{ - char *s = nd_get_link(nd); - - p9_debug(P9_DEBUG_VFS, " %pd %s\n", - dentry, IS_ERR(s) ? "" : s); - if (!IS_ERR(s)) - __putname(s); -} - -/** * v9fs_vfs_mkspecial - create a special file * @dir: inode to create special file in * @dentry: dentry to create @@ -1514,7 +1457,7 @@ static const struct inode_operations v9fs_file_inode_operations = { static const struct inode_operations v9fs_symlink_inode_operations = { .readlink = generic_readlink, .follow_link = v9fs_vfs_follow_link, - .put_link = v9fs_vfs_put_link, + .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c index 9861c7c..bc2a91f 100644 --- a/fs/9p/vfs_inode_dotl.c +++ b/fs/9p/vfs_inode_dotl.c @@ -912,33 +912,18 @@ error: static void * v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd) { - int retval; - struct p9_fid *fid; - char *link = __getname(); + struct p9_fid *fid = v9fs_fid_lookup(dentry); char *target; + int retval; p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); - if (!link) { - link = ERR_PTR(-ENOMEM); - goto ndset; - } - fid = v9fs_fid_lookup(dentry); - if (IS_ERR(fid)) { - __putname(link); - link = ERR_CAST(fid); - goto ndset; - } + if (IS_ERR(fid)) + return ERR_CAST(fid); retval = p9_client_readlink(fid, &target); - if (!retval) { - strcpy(link, target); - kfree(target); - goto ndset; - } - __putname(link); - link = ERR_PTR(retval); -ndset: - nd_set_link(nd, link); + if (retval) + return ERR_PTR(retval); + nd_set_link(nd, target); return NULL; } @@ -1006,7 +991,7 @@ const struct inode_operations v9fs_file_inode_operations_dotl = { const struct inode_operations v9fs_symlink_inode_operations_dotl = { .readlink = generic_readlink, .follow_link = v9fs_vfs_follow_link_dotl, - .put_link = v9fs_vfs_put_link, + .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr_dotl, .setattr = v9fs_vfs_setattr_dotl, .setxattr = generic_setxattr,