linux-kernel - [PATCH V2 1/1] ecryptfs: call vfs_setxattr() in ecryptfs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <201010051853.52231.roberto.sassu@polito.it>
Date:	Tue, 5 Oct 2010 18:53:45 +0200
From:	Roberto Sassu <roberto.sassu@...ito.it>
To:	tyhicks@...ux.vnet.ibm.com, kirkland@...onical.com,
	jmorris@...ei.org, akpm@...ux-foundation.org,
	linux-security-module@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH V2 1/1] ecryptfs: call vfs_setxattr() in ecryptfs_setxattr()

Ecryptfs is a stackable filesystem which relies on lower filesystems the
ability of setting/getting extended attributes.

If there is a security module enabled on the system it updates the
'security' field of inodes according to the owned extended attribute set
with the function vfs_setxattr().  When this function is performed on a
ecryptfs filesystem the 'security' field is not updated for the lower
filesystem since the call security_inode_post_setxattr() is missing for
the lower inode.
Further, the call security_inode_setxattr() is missing for the lower inode,
leading to policy violations in the security module because specific
checks for this hook are not performed (i. e. filesystem 
'associate' permission on SELinux is not checked for the lower filesystem).

This patch replaces the call of the setxattr() method of the lower inode
in the function ecryptfs_setxattr() with vfs_setxattr().

Signed-off-by: Roberto Sassu <roberto.sassu@...ito.it>
Reviewed-by: Tyler Hicks <tyhicks@...ux.vnet.ibm.com>
---
 fs/ecryptfs/inode.c |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 8cd617b..9c0cc4b 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -32,6 +32,7 @@
 #include <linux/crypto.h>
 #include <linux/fs_stack.h>
 #include <linux/slab.h>
+#include <linux/xattr.h>
 #include <asm/unaligned.h>
 #include "ecryptfs_kernel.h"

@@ -1016,10 +1017,8 @@ ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 		rc = -EOPNOTSUPP;
 		goto out;
 	}
-	mutex_lock(&lower_dentry->d_inode->i_mutex);
-	rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, name, value,
-						   size, flags);
-	mutex_unlock(&lower_dentry->d_inode->i_mutex);
+
+	rc = vfs_setxattr(lower_dentry, name, value, size, flags);
 out:
 	return rc;
 }
-- 
1.7.2.3

Download attachment "smime.p7s" of type "application/pkcs7-signature" (4707 bytes)