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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 61991C43381 for ; Fri, 15 Feb 2019 02:38:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3110221927 for ; Fri, 15 Feb 2019 02:38:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550198328; bh=yZNbZjN7ovG387jir/AvXsVTD4boIgpK7fDBSrNLyHA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WHvsVwzfrXweUfQERutZ0SFpk9XmgXQQrtkPaCbgFtr2lwG7z+b6aSnppk+Uwe4j5 AmTxiGlJFYaDPn1z8k2VXDqN/wNearIuOgQXWtn/V+7Qful/4dQrb/Al+4Vm7AYgEa 2+mF8hvSmd8JWyh2qozSc2ESwxG4VnR2yFA6sJ6c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390332AbfBOCKY (ORCPT ); Thu, 14 Feb 2019 21:10:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:50516 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390248AbfBOCKX (ORCPT ); Thu, 14 Feb 2019 21:10:23 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 362F0206BA; Fri, 15 Feb 2019 02:10:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550196622; bh=yZNbZjN7ovG387jir/AvXsVTD4boIgpK7fDBSrNLyHA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FDzfQMhwnf0gRRU+Ecj2pD2qUez6dbPHMD/ib01EwW0OA0WBJ1IHSIrnhufzcr2Dg fWJhvUhzG9//bV8YFfX1kbGqkYDfJ1QCmDrCP3Vo5rR6dVmMkBeOzIEH36Ik3f1t1N donsxWb0/bfCwey2zbso7JEsobNzzyvL+xS2GZv4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Ewan D. Milne" , "Martin K . Petersen" , Sasha Levin , linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 4.20 51/77] scsi: lpfc: nvme: avoid hang / use-after-free when destroying localport Date: Thu, 14 Feb 2019 21:08:29 -0500 Message-Id: <20190215020855.176727-51-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190215020855.176727-1-sashal@kernel.org> References: <20190215020855.176727-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: "Ewan D. Milne" [ Upstream commit 7961cba6f7d8215fa632df3d220e5154bb825249 ] We cannot wait on a completion object in the lpfc_nvme_lport structure in the _destroy_localport() code path because the NVMe/fc transport will free that structure immediately after the .localport_delete() callback. This results in a use-after-free, and a hang if slub_debug=FZPU is enabled. Fix this by putting the completion on the stack. Signed-off-by: Ewan D. Milne Acked-by: James Smart Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/lpfc/lpfc_nvme.c | 16 +++++++++------- drivers/scsi/lpfc/lpfc_nvme.h | 2 +- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c index ba831def9301..b6fe88de372a 100644 --- a/drivers/scsi/lpfc/lpfc_nvme.c +++ b/drivers/scsi/lpfc/lpfc_nvme.c @@ -297,7 +297,8 @@ lpfc_nvme_localport_delete(struct nvme_fc_local_port *localport) lport); /* release any threads waiting for the unreg to complete */ - complete(&lport->lport_unreg_done); + if (lport->vport->localport) + complete(lport->lport_unreg_cmp); } /* lpfc_nvme_remoteport_delete @@ -2547,7 +2548,8 @@ lpfc_nvme_create_localport(struct lpfc_vport *vport) */ void lpfc_nvme_lport_unreg_wait(struct lpfc_vport *vport, - struct lpfc_nvme_lport *lport) + struct lpfc_nvme_lport *lport, + struct completion *lport_unreg_cmp) { #if (IS_ENABLED(CONFIG_NVME_FC)) u32 wait_tmo; @@ -2559,8 +2561,7 @@ lpfc_nvme_lport_unreg_wait(struct lpfc_vport *vport, */ wait_tmo = msecs_to_jiffies(LPFC_NVME_WAIT_TMO * 1000); while (true) { - ret = wait_for_completion_timeout(&lport->lport_unreg_done, - wait_tmo); + ret = wait_for_completion_timeout(lport_unreg_cmp, wait_tmo); if (unlikely(!ret)) { lpfc_printf_vlog(vport, KERN_ERR, LOG_NVME_IOERR, "6176 Lport %p Localport %p wait " @@ -2594,12 +2595,12 @@ lpfc_nvme_destroy_localport(struct lpfc_vport *vport) struct lpfc_nvme_lport *lport; struct lpfc_nvme_ctrl_stat *cstat; int ret; + DECLARE_COMPLETION_ONSTACK(lport_unreg_cmp); if (vport->nvmei_support == 0) return; localport = vport->localport; - vport->localport = NULL; lport = (struct lpfc_nvme_lport *)localport->private; cstat = lport->cstat; @@ -2610,13 +2611,14 @@ lpfc_nvme_destroy_localport(struct lpfc_vport *vport) /* lport's rport list is clear. Unregister * lport and release resources. */ - init_completion(&lport->lport_unreg_done); + lport->lport_unreg_cmp = &lport_unreg_cmp; ret = nvme_fc_unregister_localport(localport); /* Wait for completion. This either blocks * indefinitely or succeeds */ - lpfc_nvme_lport_unreg_wait(vport, lport); + lpfc_nvme_lport_unreg_wait(vport, lport, &lport_unreg_cmp); + vport->localport = NULL; kfree(cstat); /* Regardless of the unregister upcall response, clear diff --git a/drivers/scsi/lpfc/lpfc_nvme.h b/drivers/scsi/lpfc/lpfc_nvme.h index cfd4719be25c..b234d0298994 100644 --- a/drivers/scsi/lpfc/lpfc_nvme.h +++ b/drivers/scsi/lpfc/lpfc_nvme.h @@ -50,7 +50,7 @@ struct lpfc_nvme_ctrl_stat { /* Declare nvme-based local and remote port definitions. */ struct lpfc_nvme_lport { struct lpfc_vport *vport; - struct completion lport_unreg_done; + struct completion *lport_unreg_cmp; /* Add stats counters here */ struct lpfc_nvme_ctrl_stat *cstat; atomic_t fc4NvmeLsRequests; -- 2.19.1