From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933224AbcBIAIA (ORCPT ); Mon, 8 Feb 2016 19:08:00 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:59842 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932199AbcBHXyj (ORCPT ); Mon, 8 Feb 2016 18:54:39 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Vasily Averin" , "Steve French" Date: Mon, 08 Feb 2016 23:53:51 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 52/87] cifs_dbg() outputs an uninitialized buffer in cifs_readdir() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:a11:96ff:fe28:a980 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.77-rc1 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 [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- fs/cifs/readdir.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/cifs/readdir.c +++ b/fs/cifs/readdir.c @@ -823,6 +823,7 @@ int cifs_readdir(struct file *file, void } /* if buggy server returns . and .. late do we want to check for that here? */ + *tmp_buf = 0; rc = cifs_filldir(current_entry, file, filldir, direntry, tmp_buf, max_len); if (rc == -EOVERFLOW) {