From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932952AbcBCXWA (ORCPT ); Wed, 3 Feb 2016 18:22:00 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:46920 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932587AbcBCWgo (ORCPT ); Wed, 3 Feb 2016 17:36:44 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Vasily Averin , Steve French , Luis Henriques Subject: [PATCH 3.16.y-ckt 106/180] cifs_dbg() outputs an uninitialized buffer in cifs_readdir() Date: Wed, 3 Feb 2016 22:31:52 +0000 Message-Id: <1454538786-12215-107-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1454538786-12215-1-git-send-email-luis.henriques@canonical.com> References: <1454538786-12215-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt24 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ 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: Luis Henriques --- fs/cifs/readdir.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c index b334a89d6a66..1320d1ecc630 100644 --- a/fs/cifs/readdir.c +++ b/fs/cifs/readdir.c @@ -849,6 +849,7 @@ int cifs_readdir(struct file *file, struct dir_context *ctx) * 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) {