2008-06-16 11:46:58

by Miklos Szeredi

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Subject: [patch] sysfs: don't call notify_change

Greg,

Could you please take this patch into your 2.6.27 queue?

Thanks,
Miklos

--
From: Miklos Szeredi <[email protected]>

sysfs_chmod_file() calls notify_change() to change the permission bits
on a sysfs file. Replace with explicit call to sysfs_setattr() and
fsnotify_change().

This is equivalent, except that security_inode_setattr() is not
called. This function is called by drivers, so the security checks do
not make any sense.

Signed-off-by: Miklos Szeredi <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
---
fs/sysfs/file.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

Index: linux-2.6/fs/sysfs/file.c
===================================================================
--- linux-2.6.orig/fs/sysfs/file.c 2008-06-09 19:16:45.000000000 +0200
+++ linux-2.6/fs/sysfs/file.c 2008-06-09 19:49:49.000000000 +0200
@@ -14,6 +14,7 @@
#include <linux/kobject.h>
#include <linux/kallsyms.h>
#include <linux/slab.h>
+#include <linux/fsnotify.h>
#include <linux/namei.h>
#include <linux/poll.h>
#include <linux/list.h>
@@ -585,9 +586,11 @@ int sysfs_chmod_file(struct kobject *kob

newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- rc = notify_change(victim, &newattrs);
+ newattrs.ia_ctime = current_fs_time(inode->i_sb);
+ rc = sysfs_setattr(victim, &newattrs);

if (rc == 0) {
+ fsnotify_change(victim, newattrs.ia_valid);
mutex_lock(&sysfs_mutex);
victim_sd->s_mode = newattrs.ia_mode;
mutex_unlock(&sysfs_mutex);


2008-06-16 22:30:37

by Greg KH

[permalink] [raw]
Subject: Re: [patch] sysfs: don't call notify_change

On Mon, Jun 16, 2008 at 01:46:47PM +0200, Miklos Szeredi wrote:
> Greg,
>
> Could you please take this patch into your 2.6.27 queue?

Sure, would be glad to.

thanks,

greg k-h