From patchwork Mon Aug 3 12:19:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 266845 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AD83C433E0 for ; Mon, 3 Aug 2020 12:42:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BEEC20738 for ; Mon, 3 Aug 2020 12:42:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596458524; bh=yjdHc/3RhY1oNsnLLVQljljiujWDhRGpXIEJ97lP+S0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xMesvOfCV2aoDrxuAfrp+pVMix54bjCNa4duCBKj6jSroohOiA8gu3n8DBu6BsUgf IUbD8v6gQNGPpxkZ31ya0lTxKzkfn7POqVp+6W56ov9VBZc5r683b9q7Rt+HnvFkB3 Nf6c+f5ZptTfRyrXUnXjxdoAE3foaFP5usoZPXLY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728401AbgHCMlv (ORCPT ); Mon, 3 Aug 2020 08:41:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:59928 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728803AbgHCMcE (ORCPT ); Mon, 3 Aug 2020 08:32:04 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3B74120775; Mon, 3 Aug 2020 12:32:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596457922; bh=yjdHc/3RhY1oNsnLLVQljljiujWDhRGpXIEJ97lP+S0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OJn2oIUrAxOYrecaASbWLtxw6Q5eJf0Hx8J+4Ma8bNwKH4kOQhQmGJYNt3MQVO9R0 WqJeryFQmbzgnES8yveuvSo4a9li864pkaaLqBhk+r1cfBsc8ag++ujh7TFIqZU6fM nDR+H+D6foUcz+aJyTEBmESX2BkebhZwqCUiWb94= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Peilin Ye , Santosh Shilimkar , "David S. Miller" Subject: [PATCH 4.19 23/56] rds: Prevent kernel-infoleak in rds_notify_queue_get() Date: Mon, 3 Aug 2020 14:19:38 +0200 Message-Id: <20200803121851.460373765@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200803121850.306734207@linuxfoundation.org> References: <20200803121850.306734207@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peilin Ye commit bbc8a99e952226c585ac17477a85ef1194501762 upstream. rds_notify_queue_get() is potentially copying uninitialized kernel stack memory to userspace since the compiler may leave a 4-byte hole at the end of `cmsg`. In 2016 we tried to fix this issue by doing `= { 0 };` on `cmsg`, which unfortunately does not always initialize that 4-byte hole. Fix it by using memset() instead. Cc: stable@vger.kernel.org Fixes: f037590fff30 ("rds: fix a leak of kernel memory") Fixes: bdbe6fbc6a2f ("RDS: recv.c") Suggested-by: Dan Carpenter Signed-off-by: Peilin Ye Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rds/recv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/rds/recv.c +++ b/net/rds/recv.c @@ -455,12 +455,13 @@ static int rds_still_queued(struct rds_s int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msghdr) { struct rds_notifier *notifier; - struct rds_rdma_notify cmsg = { 0 }; /* fill holes with zero */ + struct rds_rdma_notify cmsg; unsigned int count = 0, max_messages = ~0U; unsigned long flags; LIST_HEAD(copy); int err = 0; + memset(&cmsg, 0, sizeof(cmsg)); /* fill holes with zero */ /* put_cmsg copies to user space and thus may sleep. We can't do this * with rs_lock held, so first grab as many notifications as we can stuff