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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 D12AFC3A589 for ; Mon, 19 Aug 2019 01:53:43 +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 7A2872184D for ; Mon, 19 Aug 2019 01:53:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A2872184D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru 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 46BcQq2c61zDr8r for ; Mon, 19 Aug 2019 11:53:39 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=ozlabs.ru (client-ip=107.173.13.209; helo=ozlabs.ru; envelope-from=aik@ozlabs.ru; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru Received: from ozlabs.ru (ozlabs.ru [107.173.13.209]) by lists.ozlabs.org (Postfix) with ESMTP id 46BcNn2Wk4zDqdc for ; Mon, 19 Aug 2019 11:51:52 +1000 (AEST) Received: from fstn1-p1.ozlabs.ibm.com (localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id 0CA6BAE8001C; Sun, 18 Aug 2019 21:51:00 -0400 (EDT) From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH kernel] vfio/spapr_tce: Fix incorrect tce_iommu_group memory free Date: Mon, 19 Aug 2019 11:51:17 +1000 Message-Id: <20190819015117.94878-1-aik@ozlabs.ru> X-Mailer: git-send-email 2.17.1 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: kvm@vger.kernel.org, Jose Ricardo Ziviani , Alexey Kardashevskiy , kvm-ppc@vger.kernel.org, Alex Williamson , David Gibson Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" The @tcegrp variable is used in 1) a loop over attached groups 2) it stores a pointer to a newly allocated tce_iommu_group if 1) found nothing. However the error handler does not distinguish how we got there and incorrectly releases memory for a found+incompatible group. This fixes it by adding another error handling case. Fixes: 0bd971676e68 ("powerpc/powernv/npu: Add compound IOMMU groups") Signed-off-by: Alexey Kardashevskiy --- The bug is there since 2157e7b82f3b but it would not appear in practice before 0bd971676e68, hence that "Fixes". Or it still should be 157e7b82f3b ("vfio: powerpc/spapr: Register memory and define IOMMU v2") ? Found it when tried adding a "compound PE" (GPU + NPUs) to a container with a passed through xHCI host. The compatibility test (->create_table should be equal) treats them as incompatible which might a bug (or we are just suboptimal here) on its own. --- drivers/vfio/vfio_iommu_spapr_tce.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index 8ce9ad21129f..babef8b00daf 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1234,7 +1234,7 @@ static long tce_iommu_take_ownership_ddw(struct tce_container *container, static int tce_iommu_attach_group(void *iommu_data, struct iommu_group *iommu_group) { - int ret; + int ret = 0; struct tce_container *container = iommu_data; struct iommu_table_group *table_group; struct tce_iommu_group *tcegrp = NULL; @@ -1287,13 +1287,13 @@ static int tce_iommu_attach_group(void *iommu_data, !table_group->ops->release_ownership) { if (container->v2) { ret = -EPERM; - goto unlock_exit; + goto free_exit; } ret = tce_iommu_take_ownership(container, table_group); } else { if (!container->v2) { ret = -EPERM; - goto unlock_exit; + goto free_exit; } ret = tce_iommu_take_ownership_ddw(container, table_group); if (!tce_groups_attached(container) && !container->tables[0]) @@ -1305,10 +1305,11 @@ static int tce_iommu_attach_group(void *iommu_data, list_add(&tcegrp->next, &container->group_list); } -unlock_exit: +free_exit: if (ret && tcegrp) kfree(tcegrp); +unlock_exit: mutex_unlock(&container->lock); return ret; -- 2.17.1