From: ebiederm@xmission.com (Eric W. Biederman)
To: <linux-kernel@vger.kernel.org>
Cc: <linux-fsdevel@vger.kernel.org>, <netdev@vger.kernel.org>,
Lucian Adrian Grijincu <lucian.grijincu@gmail.com>,
Damien Millescamps <damien.millescamps@6wind.com>,
Dan Carpenter <dan.carpenter@oracle.com>
Subject: [PATCH 4/4] sysctl: Don't call sysctl_follow_link unless we are a link.
Date: Wed, 01 Feb 2012 19:30:04 -0800 [thread overview]
Message-ID: <m1liolvrnn.fsf_-_@fess.ebiederm.org> (raw)
In-Reply-To: <m139atx6bs.fsf@fess.ebiederm.org> (Eric W. Biederman's message of "Wed, 01 Feb 2012 19:27:51 -0800")
There are no functional changes. Just code motion to make it
clear that we don't follow a link between sysctl roots unless the
directory entry actually is a link.
Suggested-by: Lucian Adrian Grijincu <lucian.grijincu@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
fs/proc/proc_sysctl.c | 24 ++++++++++++------------
1 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index e5601dc..a7708b7 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -451,10 +451,12 @@ static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry,
if (!p)
goto out;
- ret = sysctl_follow_link(&h, &p, current->nsproxy);
- err = ERR_PTR(ret);
- if (ret)
- goto out;
+ if (S_ISLNK(p->mode)) {
+ ret = sysctl_follow_link(&h, &p, current->nsproxy);
+ err = ERR_PTR(ret);
+ if (ret)
+ goto out;
+ }
err = ERR_PTR(-ENOMEM);
inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p);
@@ -601,10 +603,12 @@ static int proc_sys_link_fill_cache(struct file *filp, void *dirent,
int err, ret = 0;
head = sysctl_head_grab(head);
- /* It is not an error if we can not follow the link ignore it */
- err = sysctl_follow_link(&head, &table, current->nsproxy);
- if (err)
- goto out;
+ if (S_ISLNK(table->mode)) {
+ /* It is not an error if we can not follow the link ignore it */
+ err = sysctl_follow_link(&head, &table, current->nsproxy);
+ if (err)
+ goto out;
+ }
ret = proc_sys_fill_cache(filp, dirent, filldir, head, table);
out:
@@ -950,10 +954,6 @@ static int sysctl_follow_link(struct ctl_table_header **phead,
struct ctl_dir *dir;
int ret;
- /* Get out quickly if not a link */
- if (!S_ISLNK((*pentry)->mode))
- return 0;
-
ret = 0;
spin_lock(&sysctl_lock);
root = (*pentry)->data;
--
1.7.2.5
prev parent reply other threads:[~2012-02-02 3:30 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-27 4:45 [Review][PATCH][0/29] sysctl rewrite for speed and clarity Eric W. Biederman
2012-01-27 4:49 ` [PATCH 01/29] sysctl: remove impossible condition check Eric W. Biederman
2012-01-27 4:49 ` [PATCH 02/29] sysctl: Consolidate !CONFIG_SYSCTL handling Eric W. Biederman
2012-01-27 4:49 ` [PATCH 03/29] sysctl: Register the base sysctl table like any other sysctl table Eric W. Biederman
2012-01-27 4:49 ` [PATCH 04/29] sysctl: Move the implementation into fs/proc/proc_sysctl.c Eric W. Biederman
2012-01-27 4:49 ` [PATCH 05/29] sysctl: Make the directories have nlink == 1 Eric W. Biederman
2012-01-27 4:49 ` [PATCH 06/29] sysctl: Implement retire_sysctl_set Eric W. Biederman
2012-01-27 4:49 ` [PATCH 07/29] sysctl: Remove the unnecessary sysctl_set parent concept Eric W. Biederman
2012-01-27 4:49 ` [PATCH 08/29] sysctl: Create local copies of directory names used in paths Eric W. Biederman
2012-01-27 4:49 ` [PATCH 09/29] sysctl: Add support for register sysctl tables with a normal cstring path Eric W. Biederman
2012-01-27 4:49 ` [PATCH 10/29] sysctl: Add ctl_table chains into cstring paths Eric W. Biederman
2012-01-27 4:49 ` [PATCH 11/29] sysctl: register only tables of sysctl files Eric W. Biederman
2012-01-27 4:49 ` [PATCH 12/29] sysctl: Improve the sysctl sanity checks Eric W. Biederman
2012-01-27 4:49 ` [PATCH 13/29] sysctl: Remove the now unused ctl_table parent field Eric W. Biederman
2012-01-27 4:49 ` [PATCH 14/29] sysctl: A more obvious version of grab_header Eric W. Biederman
2012-01-27 4:49 ` [PATCH 15/29] sysctl: Initial support for auto-unregistering sysctl tables Eric W. Biederman
2012-01-27 4:49 ` [PATCH 16/29] sysctl: Factor out init_header from __register_sysctl_paths Eric W. Biederman
2012-01-27 4:49 ` [PATCH 17/29] sysctl: Factor out insert_header and erase_header Eric W. Biederman
2012-01-27 4:49 ` [PATCH 18/29] sysctl: Normalize the root_table data structure Eric W. Biederman
2012-01-27 4:50 ` [PATCH 19/29] sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry Eric W. Biederman
2012-01-27 4:50 ` [PATCH 20/29] sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry Eric W. Biederman
2012-01-27 4:50 ` [PATCH 21/29] sysctl: Add a root pointer to ctl_table_set Eric W. Biederman
2012-01-27 4:50 ` [PATCH 22/29] sysctl: Stop requiring explicit management of sysctl directories Eric W. Biederman
2012-01-27 4:50 ` [PATCH 23/29] sysctl: Add sysctl_print_dir and use it in get_subdir Eric W. Biederman
2012-01-27 4:50 ` [PATCH 24/29] sysctl: Replace root_list with links between sysctl_table_sets Eric W. Biederman
2012-01-27 4:50 ` [PATCH 25/29] sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy Eric W. Biederman
2012-01-27 4:50 ` [PATCH 26/29] sysctl: Move sysctl_check_dups into insert_header Eric W. Biederman
2012-01-27 4:50 ` [PATCH 27/29] sysctl: Make the header lists per directory Eric W. Biederman
2012-01-27 4:50 ` [PATCH 28/29] sysctl: Index sysctl directories with rbtrees Eric W. Biederman
2012-01-27 4:50 ` [PATCH 29/29] sysctl: Add register_sysctl for normal sysctl users Eric W. Biederman
2012-01-27 4:51 ` [PATCH 01/29] sysctl: remove impossible condition check Eric W. Biederman
2012-01-27 4:51 ` [PATCH 02/29] sysctl: Consolidate !CONFIG_SYSCTL handling Eric W. Biederman
2012-01-27 4:51 ` [PATCH 03/29] sysctl: Register the base sysctl table like any other sysctl table Eric W. Biederman
2012-01-27 4:51 ` [PATCH 04/29] sysctl: Move the implementation into fs/proc/proc_sysctl.c Eric W. Biederman
2012-01-27 4:51 ` [PATCH 05/29] sysctl: Make the directories have nlink == 1 Eric W. Biederman
2012-01-27 4:51 ` [PATCH 06/29] sysctl: Implement retire_sysctl_set Eric W. Biederman
2012-01-27 4:51 ` [PATCH 07/29] sysctl: Remove the unnecessary sysctl_set parent concept Eric W. Biederman
2012-01-27 4:51 ` [PATCH 08/29] sysctl: Create local copies of directory names used in paths Eric W. Biederman
2012-01-27 4:51 ` [PATCH 09/29] sysctl: Add support for register sysctl tables with a normal cstring path Eric W. Biederman
2012-01-27 4:51 ` [PATCH 10/29] sysctl: Add ctl_table chains into cstring paths Eric W. Biederman
2012-01-27 4:51 ` [PATCH 11/29] sysctl: register only tables of sysctl files Eric W. Biederman
2012-01-27 4:51 ` [PATCH 12/29] sysctl: Improve the sysctl sanity checks Eric W. Biederman
2012-01-27 4:51 ` [PATCH 13/29] sysctl: Remove the now unused ctl_table parent field Eric W. Biederman
2012-01-27 4:51 ` [PATCH 14/29] sysctl: A more obvious version of grab_header Eric W. Biederman
2012-01-27 4:51 ` [PATCH 15/29] sysctl: Initial support for auto-unregistering sysctl tables Eric W. Biederman
2012-01-27 4:51 ` [PATCH 16/29] sysctl: Factor out init_header from __register_sysctl_paths Eric W. Biederman
2012-01-27 4:51 ` [PATCH 17/29] sysctl: Factor out insert_header and erase_header Eric W. Biederman
2012-01-27 4:51 ` [PATCH 18/29] sysctl: Normalize the root_table data structure Eric W. Biederman
2012-01-29 17:36 ` Lucian Adrian Grijincu
2012-01-30 0:22 ` Eric W. Biederman
2012-01-27 4:51 ` [PATCH 19/29] sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry Eric W. Biederman
2012-01-29 15:49 ` Lucian Adrian Grijincu
2012-01-27 4:51 ` [PATCH 20/29] sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry Eric W. Biederman
2012-01-27 4:51 ` [PATCH 21/29] sysctl: Add a root pointer to ctl_table_set Eric W. Biederman
2012-01-29 17:19 ` Lucian Adrian Grijincu
2012-01-27 4:51 ` [PATCH 22/29] sysctl: Stop requiring explicit management of sysctl directories Eric W. Biederman
2012-01-29 19:31 ` Lucian Adrian Grijincu
2012-01-31 4:45 ` Eric W. Biederman
2012-01-27 4:51 ` [PATCH 23/29] sysctl: Add sysctl_print_dir and use it in get_subdir Eric W. Biederman
2012-01-27 4:52 ` [PATCH 24/29] sysctl: Replace root_list with links between sysctl_table_sets Eric W. Biederman
2012-01-30 0:01 ` Lucian Adrian Grijincu
2012-01-31 3:10 ` Eric W. Biederman
2012-01-30 17:51 ` Dave Jones
2012-01-31 2:11 ` Eric W. Biederman
2012-01-31 2:13 ` Joe Perches
2012-01-27 4:52 ` [PATCH 25/29] sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy Eric W. Biederman
2012-01-27 4:52 ` [PATCH 26/29] sysctl: Move sysctl_check_dups into insert_header Eric W. Biederman
2012-01-27 4:52 ` [PATCH 27/29] sysctl: Make the header lists per directory Eric W. Biederman
2012-01-27 4:52 ` [PATCH 28/29] sysctl: Index sysctl directories with rbtrees Eric W. Biederman
2012-01-27 4:52 ` [PATCH 29/29] sysctl: Add register_sysctl for normal sysctl users Eric W. Biederman
2012-02-02 3:27 ` [Review][PATCH][0/4] sysctl bitty fixes Eric W. Biederman
2012-02-02 3:28 ` [PATCH 1/4] sysctl: An easier to read version of find_subdir Eric W. Biederman
2012-02-02 3:29 ` [PATCH 2/4] sysctl: Correct error return from get_subdir Eric W. Biederman
2012-02-02 3:29 ` [PATCH 3/4] sysctl: Comments to make the code clearer Eric W. Biederman
2012-02-02 16:28 ` Ben Hutchings
2012-02-02 3:30 ` Eric W. Biederman [this message]
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