staging/lustre: fix permission problem of setfacl

Setxattr does not check the permission when setting ACL xattrs. This
will cause security problem because any user can walk around
permission checking by changing ACL rules.

Signed-off-by: Li Xi <lixi@ddn.com>
Reviewed-on: http://review.whamcloud.com/9473
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4704
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/llite/xattr.c b/drivers/staging/lustre/lustre/llite/xattr.c
index b1ed4d9..67a1de4 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/xattr.c
+++ b/drivers/staging/lustre/lustre/llite/xattr.c
@@ -124,6 +124,11 @@ int ll_setxattr_common(struct inode *inode, const char *name,
        if (rc)
                return rc;
 
+       if ((xattr_type == XATTR_ACL_ACCESS_T ||
+            xattr_type == XATTR_ACL_DEFAULT_T) &&
+           !inode_owner_or_capable(inode))
+               return -EPERM;
+
        /* b10667: ignore lustre special xattr for now */
        if ((xattr_type == XATTR_TRUSTED_T && strcmp(name, "trusted.lov") == 0) ||
            (xattr_type == XATTR_LUSTRE_T && strcmp(name, "lustre.lov") == 0))