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=-6.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no 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 075B1C433E1 for ; Wed, 26 Aug 2020 00:33:04 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7ACFC20707 for ; Wed, 26 Aug 2020 00:33:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7ACFC20707 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4Bbmzc75SBzDqZS for ; Wed, 26 Aug 2020 10:33:00 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=davemloft.net (client-ip=2620:137:e000::1:9; helo=shards.monkeyblade.net; envelope-from=davem@davemloft.net; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=davemloft.net Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Bbmxl3bFXzDqWn for ; Wed, 26 Aug 2020 10:31:19 +1000 (AEST) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 014C211E44280; Tue, 25 Aug 2020 17:14:18 -0700 (PDT) Date: Tue, 25 Aug 2020 17:31:04 -0700 (PDT) Message-Id: <20200825.173104.1541443546408114168.davem@davemloft.net> To: drt@linux.ibm.com Subject: Re: [PATCH net v3] ibmvnic fix NULL tx_pools and rx_tools issue at do_reset From: David Miller In-Reply-To: <20200825172641.806912-1-drt@linux.ibm.com> References: <20200825172641.806912-1-drt@linux.ibm.com> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 25 Aug 2020 17:14:19 -0700 (PDT) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: netdev@vger.kernel.org, mmc@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Dany Madden Date: Tue, 25 Aug 2020 13:26:41 -0400 > From: Mingming Cao > > At the time of do_rest, ibmvnic tries to re-initalize the tx_pools > and rx_pools to avoid re-allocating the long term buffer. However > there is a window inside do_reset that the tx_pools and > rx_pools were freed before re-initialized making it possible to deference > null pointers. > > This patch fix this issue by always check the tx_pool > and rx_pool are not NULL after ibmvnic_login. If so, re-allocating > the pools. This will avoid getting into calling reset_tx/rx_pools with > NULL adapter tx_pools/rx_pools pointer. Also add null pointer check in > reset_tx_pools and reset_rx_pools to safe handle NULL pointer case. > > Signed-off-by: Mingming Cao > Signed-off-by: Dany Madden Applied, but: > + if (!adapter->rx_pool) > + return -1; > + This driver has poor error code usage, it's a random mix of hypervisor error codes, normal error codes like -EINVAL, and internal error codes. Sometimes used all in the same function. For example: static int ibmvnic_send_crq(struct ibmvnic_adapter *adapter, union ibmvnic_crq *crq) ... if (!adapter->crq.active && crq->generic.first != IBMVNIC_CRQ_INIT_CMD) { dev_warn(dev, "Invalid request detected while CRQ is inactive, possible device state change during reset\n"); return -EINVAL; } ... rc = plpar_hcall_norets(H_SEND_CRQ, ua, cpu_to_be64(u64_crq[0]), cpu_to_be64(u64_crq[1])); if (rc) { if (rc == H_CLOSED) { ... return rc; So obviously this function returns a mix of negative erro codes and Hypervisor codes such as H_CLOSED. And stuff like: rc = __ibmvnic_open(netdev); if (rc) return IBMVNIC_OPEN_FAILED;