From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754500AbZE1XDk (ORCPT ); Thu, 28 May 2009 19:03:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753697AbZE1XCZ (ORCPT ); Thu, 28 May 2009 19:02:25 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:32848 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753838AbZE1XCV (ORCPT ); Thu, 28 May 2009 19:02:21 -0400 From: "Eric W. Biederman" To: Andrew Morton , Greg Kroah-Hartman Cc: , Tejun Heo , Cornelia Huck , , Kay Sievers , Greg KH , "Eric W. Biederman" , "Eric W. Biederman" Date: Thu, 28 May 2009 16:00:45 -0700 Message-Id: <1243551665-23596-4-git-send-email-ebiederm@xmission.com> X-Mailer: git-send-email 1.6.3.1.54.g99dd.dirty In-Reply-To: References: X-XM-SPF: eid=;;;mid=;;;hst=in01.mta.xmission.com;;;ip=76.21.114.89;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 76.21.114.89 X-SA-Exim-Rcpt-To: akpm@linux-foundation.org, gregkh@suse.de, linux-kernel@vger.kernel.org, tj@kernel.org, cornelia.huck@de.ibm.com, linux-fsdevel@vger.kernel.org, kay.sievers@vrfy.org, greg@kroah.com, ebiederm@xmission.com, ebiederm@aristanetworks.com X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa03 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;Andrew Morton , Greg Kroah-Hartman X-Spam-Relay-Country: X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -1.1 BAYES_05 BODY: Bayesian spam probability is 1 to 5% * [score: 0.0123] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 1397; Body=1 Fuz1=1 Fuz2=1] * 0.5 XM_Body_Dirty_Words Contains a dirty word * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.0 XM_SPF_Neutral SPF-Neutral * 0.4 UNTRUSTED_Relay Comes from a non-trusted relay Subject: [PATCH 04/24] sysfs: Normalize removing sysfs directories. X-SA-Exim-Version: 4.2.1 (built Thu, 25 Oct 2007 00:26:12 +0000) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric W. Biederman Individually wrap each call to sysfs_remove_one with sysfs_addrm_start and sysfs_addrm_finish this prepares for these functions to be removed. I don't change the logic of which dirents we remove. I do document what we are doing and why what we are doing it. A warning is added if we attempt to remove an non-empty directories so that users that would prevsiosly have had leaks and other problems like the scsi layer get a clear warning that there is a problem. I don't hold sysfs_mutex across the entire operation as that is unneeded for coherence at the sysfs level and some level of coordination is expected at the upper layers. Signed-off-by: Eric W. Biederman --- fs/sysfs/dir.c | 62 +++++++++++++++++++++++++++++++++++++++---------------- 1 files changed, 44 insertions(+), 18 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index b95cc07..3e3a87f 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -732,12 +732,28 @@ const struct inode_operations sysfs_dir_inode_operations = { .setattr = sysfs_setattr, }; -static void remove_dir(struct sysfs_dirent *sd) +static void remove_dir(struct sysfs_dirent *dir_sd) { struct sysfs_addrm_cxt acxt; - sysfs_addrm_start(&acxt, sd->s_parent); - sysfs_remove_one(&acxt, sd); + pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); + + /* Removing non-empty directories is not valid complain! */ + if (unlikely(dir_sd->s_dir.children)) { + struct sysfs_dirent *sd; + + WARN(1, KERN_WARNING "sysfs: removing non-empty dir: %s\n", + dir_sd->s_name); + + mutex_lock(&sysfs_mutex); + for (sd = dir_sd->s_dir.children; sd; sd = sd->s_sibling) + printk(KERN_WARNING "%s/%s\n", + dir_sd->s_name, sd->s_name); + mutex_unlock(&sysfs_mutex); + } + + sysfs_addrm_start(&acxt, dir_sd->s_parent); + sysfs_remove_one(&acxt, dir_sd); sysfs_addrm_finish(&acxt); } @@ -746,27 +762,37 @@ void sysfs_remove_subdir(struct sysfs_dirent *sd) remove_dir(sd); } +static struct sysfs_dirent *get_dirent_to_remove(struct sysfs_dirent *dir_sd) +{ + struct sysfs_dirent *sd; + + mutex_lock(&sysfs_mutex); + for (sd = dir_sd->s_dir.children; sd; sd = sd->s_sibling) { + /* Directories might be owned by someone else + * making recursive directory removal unsafe. + */ + if (sysfs_type(sd) == SYSFS_DIR) + continue; + break; + } + sysfs_get(sd); + mutex_unlock(&sysfs_mutex); + + return sd; +} static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) { struct sysfs_addrm_cxt acxt; - struct sysfs_dirent **pos; - - if (!dir_sd) - return; - - pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); - sysfs_addrm_start(&acxt, dir_sd); - pos = &dir_sd->s_dir.children; - while (*pos) { - struct sysfs_dirent *sd = *pos; + struct sysfs_dirent *sd; - if (sysfs_type(sd) != SYSFS_DIR) - sysfs_remove_one(&acxt, sd); - else - pos = &(*pos)->s_sibling; + /* Remove children that we think are safe */ + while ((sd = get_dirent_to_remove(dir_sd))) { + sysfs_addrm_start(&acxt, sd->s_parent); + sysfs_remove_one(&acxt, sd); + sysfs_addrm_finish(&acxt); + sysfs_put(sd); } - sysfs_addrm_finish(&acxt); remove_dir(dir_sd); } -- 1.6.3.1.54.g99dd.dirty