From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932219AbcBXEnc (ORCPT ); Tue, 23 Feb 2016 23:43:32 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:53068 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932156AbcBXEOW (ORCPT ); Tue, 23 Feb 2016 23:14:22 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vasily Averin , Steve French Subject: [PATCH 4.4 053/137] cifs_dbg() outputs an uninitialized buffer in cifs_readdir() Date: Tue, 23 Feb 2016 19:33:04 -0800 Message-Id: <20160224033418.969860645@linuxfoundation.org> X-Mailer: git-send-email 2.7.1 In-Reply-To: <20160224033417.270530882@linuxfoundation.org> References: <20160224033417.270530882@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vasily Averin commit 01b9b0b28626db4a47d7f48744d70abca9914ef1 upstream. In some cases tmp_bug can be not filled in cifs_filldir and stay uninitialized, therefore its printk with "%s" modifier can leak content of kernelspace memory. If old content of this buffer does not contain '\0' access bejond end of allocated object can crash the host. Signed-off-by: Vasily Averin Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/cifs/readdir.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/cifs/readdir.c +++ b/fs/cifs/readdir.c @@ -847,6 +847,7 @@ int cifs_readdir(struct file *file, stru * if buggy server returns . and .. late do we want to * check for that here? */ + *tmp_buf = 0; rc = cifs_filldir(current_entry, file, ctx, tmp_buf, max_len); if (rc) {