From patchwork Tue Apr 12 22:19:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Smart X-Patchwork-Id: 563032 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3E07C433F5 for ; Tue, 12 Apr 2022 23:34:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231256AbiDLXg5 (ORCPT ); Tue, 12 Apr 2022 19:36:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231324AbiDLXct (ORCPT ); Tue, 12 Apr 2022 19:32:49 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2DF9C559A for ; Tue, 12 Apr 2022 15:20:21 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id k14so3527pga.0 for ; Tue, 12 Apr 2022 15:20:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=dpJwyubmEEG4q6uBrYJoCQzzFk49i1eY4Z47w3D6rPQ=; b=dDSHNAbz5K0fqBG5jatye8OSA+KVSM2JXxg6pjrvD5NGcEOEqrj34BDIQSfy5eCDhl VTvo/sJRWsGWraVSSj884TEH5AMLjcOeQThLeBUwNHVMtgveNNrm6aA//a5Yj5Mq2G7B lLpHq0fIJNRX0cbF+fope5SB9D95ND4e7CjO+ZBGJbNVzs92PS36dXC3rpC4wEv+3kcW ssttPrjmdbS/1J7JrOCgMdkbjxlJcTDrKHd+fRIr1SVe/SuZq2J97iAB03p9GuqGZBPB qm6dhgCENev/T9BSVzmZuYCA+2eKCappLCnbeOV7DGhPuEQjfuz7HBOx/4EQl11Cy8h+ bWQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=dpJwyubmEEG4q6uBrYJoCQzzFk49i1eY4Z47w3D6rPQ=; b=KZ5xJKBi7wQ4iGRn3WPBEn/dB42wC5Fmmh/I+RjZsmOG5fugUpZ3V7y822hOBpaRAH keOq0HTXYWEFXAFdCy2qnx1CiueMWu4Aq6qgB/cxD5ZG6qm7hXGslTmQorISL5XfUcgw DKGaH7hlw+Go8IR87iGlc1A3BikB2duO1FtNrjMOj+cT6/OVVTH6oowuVEP3TiKPr3kD +UKJyNtLHh01xZLrc1KlUtPHinlZu+TlB52ix8Ab8KbkA5i6uQ5YkB0Mt4XIZMCvUnTu so0PLkZD3/21Je6DfUM99WGRBLY4JJfLbjhivgZsMNuUACu+LYMJ0lOC/ehho3syQnYq H4xg== X-Gm-Message-State: AOAM5302ZYzDK0AEuusrxGUR23rkWTiddlMX0ZDfsGhEEaWccfIDkfjg 67DO6+hJk0sTsjqYRssO52qYzrIC6Ow= X-Google-Smtp-Source: ABdhPJw+mxyfRT5KklzNNZ8J44tWJ1LFZWOFsPTx0AvyTKl/Z2nBXQ2CU/WcYhshnfwVzPAAHmT6Hw== X-Received: by 2002:aa7:90d4:0:b0:4fd:acb9:8eac with SMTP id k20-20020aa790d4000000b004fdacb98eacmr39852709pfk.24.1649802021329; Tue, 12 Apr 2022 15:20:21 -0700 (PDT) Received: from mail-lvn-it-01.broadcom.com ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id g15-20020a056a000b8f00b004fa9dbf27desm40429824pfj.55.2022.04.12.15.20.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 12 Apr 2022 15:20:21 -0700 (PDT) From: James Smart To: linux-scsi@vger.kernel.org Cc: James Smart , Justin Tee Subject: [PATCH 08/26] lpfc: Fix null pointer dereference after failing to issue FLOGI and PLOGI Date: Tue, 12 Apr 2022 15:19:50 -0700 Message-Id: <20220412222008.126521-9-jsmart2021@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20220412222008.126521-1-jsmart2021@gmail.com> References: <20220412222008.126521-1-jsmart2021@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org If lpfc_issue_els_flogi() fails and returns non-zero status, the node reference count is decremented to trigger the release of the nodelist structure. However, if there is a prior registration or dev-loss-evt work pending, the node may be released prematurely. When dev-loss-evt completes, the released node is referenced causing a use-after-free null pointer dereference. Similarly, when processing non-zero ELS PLOGI completion status in lpfc_cmpl_els_plogi(), the ndlp flags are checked for a transport registration before triggering node removal. If dev-loss-evt work is pending, the node may be released prematurely and a subsequent call to lpfc_dev_loss_tmo_handler() results in a use after free ndlp dereference. Add test for pending dev-loss before decrementing the node reference count for FLOGI, PLOGI, PRLI, and ADISC handling. Co-developed-by: Justin Tee Signed-off-by: Justin Tee Signed-off-by: James Smart --- drivers/scsi/lpfc/lpfc_els.c | 51 +++++++++++++++++++++++++----------- 1 file changed, 35 insertions(+), 16 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c index 863251322715..10e534d63508 100644 --- a/drivers/scsi/lpfc/lpfc_els.c +++ b/drivers/scsi/lpfc/lpfc_els.c @@ -1533,10 +1533,13 @@ lpfc_initial_flogi(struct lpfc_vport *vport) /* Reset the Fabric flag, topology change may have happened */ vport->fc_flag &= ~FC_FABRIC; if (lpfc_issue_els_flogi(vport, ndlp, 0)) { - /* This decrement of reference count to node shall kick off - * the release of the node. + /* A node reference should be retained while registered with a + * transport or dev-loss-evt work is pending. + * Otherwise, decrement node reference to trigger release. */ - lpfc_nlp_put(ndlp); + if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD)) && + !(ndlp->nlp_flag & NLP_IN_DEV_LOSS)) + lpfc_nlp_put(ndlp); return 0; } return 1; @@ -1579,10 +1582,13 @@ lpfc_initial_fdisc(struct lpfc_vport *vport) } if (lpfc_issue_els_fdisc(vport, ndlp, 0)) { - /* decrement node reference count to trigger the release of - * the node. + /* A node reference should be retained while registered with a + * transport or dev-loss-evt work is pending. + * Otherwise, decrement node reference to trigger release. */ - lpfc_nlp_put(ndlp); + if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD)) && + !(ndlp->nlp_flag & NLP_IN_DEV_LOSS)) + lpfc_nlp_put(ndlp); return 0; } return 1; @@ -1984,6 +1990,7 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, int disc; struct serv_parm *sp = NULL; u32 ulp_status, ulp_word4, did, iotag; + bool release_node = false; /* we pass cmdiocb to state machine which needs rspiocb as well */ cmdiocb->context_un.rsp_iocb = rspiocb; @@ -2072,19 +2079,21 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, spin_unlock_irq(&ndlp->lock); goto out; } - spin_unlock_irq(&ndlp->lock); /* No PLOGI collision and the node is not registered with the * scsi or nvme transport. It is no longer an active node. Just * start the device remove process. */ if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) { - spin_lock_irq(&ndlp->lock); ndlp->nlp_flag &= ~NLP_NPR_2B_DISC; - spin_unlock_irq(&ndlp->lock); + if (!(ndlp->nlp_flag & NLP_IN_DEV_LOSS)) + release_node = true; + } + spin_unlock_irq(&ndlp->lock); + + if (release_node) lpfc_disc_state_machine(vport, ndlp, cmdiocb, NLP_EVT_DEVICE_RM); - } } else { /* Good status, call state machine */ prsp = list_entry(((struct lpfc_dmabuf *) @@ -2295,6 +2304,7 @@ lpfc_cmpl_els_prli(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, u32 loglevel; u32 ulp_status; u32 ulp_word4; + bool release_node = false; /* we pass cmdiocb to state machine which needs rspiocb as well */ cmdiocb->context_un.rsp_iocb = rspiocb; @@ -2371,14 +2381,18 @@ lpfc_cmpl_els_prli(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, * it is no longer an active node. Otherwise devloss * handles the final cleanup. */ + spin_lock_irq(&ndlp->lock); if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD)) && !ndlp->fc4_prli_sent) { - spin_lock_irq(&ndlp->lock); ndlp->nlp_flag &= ~NLP_NPR_2B_DISC; - spin_unlock_irq(&ndlp->lock); + if (!(ndlp->nlp_flag & NLP_IN_DEV_LOSS)) + release_node = true; + } + spin_unlock_irq(&ndlp->lock); + + if (release_node) lpfc_disc_state_machine(vport, ndlp, cmdiocb, NLP_EVT_DEVICE_RM); - } } else { /* Good status, call state machine. However, if another * PRLI is outstanding, don't call the state machine @@ -2750,6 +2764,7 @@ lpfc_cmpl_els_adisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, struct lpfc_nodelist *ndlp; int disc; u32 ulp_status, ulp_word4, tmo; + bool release_node = false; /* we pass cmdiocb to state machine which needs rspiocb as well */ cmdiocb->context_un.rsp_iocb = rspiocb; @@ -2816,13 +2831,17 @@ lpfc_cmpl_els_adisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb, * transport, it is no longer an active node. Otherwise * devloss handles the final cleanup. */ + spin_lock_irq(&ndlp->lock); if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) { - spin_lock_irq(&ndlp->lock); ndlp->nlp_flag &= ~NLP_NPR_2B_DISC; - spin_unlock_irq(&ndlp->lock); + if (!(ndlp->nlp_flag & NLP_IN_DEV_LOSS)) + release_node = true; + } + spin_unlock_irq(&ndlp->lock); + + if (release_node) lpfc_disc_state_machine(vport, ndlp, cmdiocb, NLP_EVT_DEVICE_RM); - } } else /* Good status, call state machine */ lpfc_disc_state_machine(vport, ndlp, cmdiocb,