From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id BC853A0540; Fri, 4 Nov 2022 09:51:47 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 5BD6D42D10; Fri, 4 Nov 2022 09:51:47 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id F0D6842D0E for ; Fri, 4 Nov 2022 09:51:45 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667551905; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ySuZH8Tfeq5v4PtUBPWvsifE4+naRF4JF5dh4C6wkrM=; b=BIclbuhKAohs4za5bFReB/v79BMpVvtYtsst1nnykvBB1x7Wmouya42fANFAAMtIo+zkeR EmMXCl671Zi90BSc7ly9UkP6v0EtjY/rwUwXan3+oMJO2Wmjec+TpvasfaMZvRlStyKwCI Uj6bKm0QMqQ1PYjeEi1OmNrV/5/hJg4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-258-2OECbx9bMFCiyDa8WvDRBw-1; Fri, 04 Nov 2022 04:51:44 -0400 X-MC-Unique: 2OECbx9bMFCiyDa8WvDRBw-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C1C633C0F221; Fri, 4 Nov 2022 08:51:43 +0000 (UTC) Received: from [10.40.208.32] (ovpn-208-32.brq.redhat.com [10.40.208.32]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 57F0549BB9A; Fri, 4 Nov 2022 08:51:42 +0000 (UTC) Message-ID: <3405c8de-150a-d8fd-d99a-b5a68b9dd815@redhat.com> Date: Fri, 4 Nov 2022 09:51:40 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.0 To: Hernan Vargas , dev@dpdk.org, gakhil@marvell.com, trix@redhat.com Cc: nicolas.chautru@intel.com, qi.z.zhang@intel.com References: <20221104035209.62109-1-hernan.vargas@intel.com> <20221104035209.62109-2-hernan.vargas@intel.com> From: Maxime Coquelin Subject: Re: [PATCH v1 1/1] baseband/acc: fix check after deref and dead code In-Reply-To: <20221104035209.62109-2-hernan.vargas@intel.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On 11/4/22 04:52, Hernan Vargas wrote: > Fix potential issue of dereferencing a pointer before null check. > Remove null check for value that could never be null. > > Coverity issue: 381646, 381631 > Fixes: 989dec301a9 ("baseband/acc100: add ring companion address") > > Signed-off-by: Hernan Vargas > --- > drivers/baseband/acc/rte_acc100_pmd.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/drivers/baseband/acc/rte_acc100_pmd.c b/drivers/baseband/acc/rte_acc100_pmd.c > index 96daef87bc..30a718916d 100644 > --- a/drivers/baseband/acc/rte_acc100_pmd.c > +++ b/drivers/baseband/acc/rte_acc100_pmd.c > @@ -4122,15 +4122,11 @@ acc100_dequeue_ldpc_enc(struct rte_bbdev_queue_data *q_data, > struct rte_bbdev_enc_op *op; > union acc_dma_desc *desc; > > - if (q == NULL) > - return 0; Can we be sure it can never be NULL? static inline uint16_t rte_bbdev_dequeue_ldpc_enc_ops(uint16_t dev_id, uint16_t queue_id, struct rte_bbdev_enc_op **ops, uint16_t num_ops) { struct rte_bbdev *dev = &rte_bbdev_devices[dev_id]; struct rte_bbdev_queue_data *q_data = &dev->data->queues[queue_id]; return dev->dequeue_ldpc_enc_ops(q_data, ops, num_ops); } If the application passes an invalid queue_id or dev_id you can easily get garbage. It may be worth adding some checks in all the helpers, to be sure dev_id is valid, and same for queue_id. We do that in Vhost library to improve robustness. I know there is this comment: " * This function does not provide any error notification to avoid the * corresponding overhead. " But to me this is not a good justification, the overhead would be minimal. Regards, Maxime > #ifdef RTE_LIBRTE_BBDEV_DEBUG > if (unlikely(ops == 0)) > return 0; > #endif > desc = q->ring_addr + (q->sw_ring_tail & q->sw_ring_wrap_mask); > - if (unlikely(desc == NULL)) > - return 0; > op = desc->req.op_addr; > if (unlikely(ops == NULL || op == NULL)) > return 0;