From mboxrd@z Thu Jan 1 00:00:00 1970 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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 A5AC2C43143 for ; Tue, 2 Oct 2018 14:08:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 75DF82083F for ; Tue, 2 Oct 2018 14:08:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 75DF82083F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729571AbeJBUwa (ORCPT ); Tue, 2 Oct 2018 16:52:30 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60750 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726717AbeJBULa (ORCPT ); Tue, 2 Oct 2018 16:11:30 -0400 Received: from localhost (24-104-73-23-ip-static.hfc.comcastbusiness.net [24.104.73.23]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id E6AFBC4D; Tue, 2 Oct 2018 13:28:08 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Leon Romanovsky , Jason Gunthorpe , Sasha Levin Subject: [PATCH 4.18 095/228] RDMA/uverbs: Dont overwrite NULL pointer with ZERO_SIZE_PTR Date: Tue, 2 Oct 2018 06:23:12 -0700 Message-Id: <20181002132505.786446480@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181002132459.032960735@linuxfoundation.org> References: <20181002132459.032960735@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Leon Romanovsky [ Upstream commit a5cc9831af05e658543593abaee45a29d061bac4 ] Number of specs is provided by user and in valid case can be equal to zero. Such argument causes to call to kcalloc() with zero-length request and in return the ZERO_SIZE_PTR is assigned. This pointer is different from NULL and makes various if (..) checks to success. Fixes: b6ba4a9aa59f ("IB/uverbs: Add support for flow counters") Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/uverbs_cmd.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -2812,6 +2812,9 @@ static struct ib_uflow_resources *flow_r if (!resources) goto err_res; + if (!num_specs) + goto out; + resources->counters = kcalloc(num_specs, sizeof(*resources->counters), GFP_KERNEL); @@ -2824,8 +2827,8 @@ static struct ib_uflow_resources *flow_r if (!resources->collection) goto err_collection; +out: resources->max = num_specs; - return resources; err_collection: