From patchwork Tue Sep 29 11:00:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 262931 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=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, 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 53252C47426 for ; Tue, 29 Sep 2020 12:37:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 04B5A20789 for ; Tue, 29 Sep 2020 12:37:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601383040; bh=YlTmgV/qZt3ZFXhDb+TKIjKiP4FvzssjohG7yDlhUtw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MesjQ3EQepNr3mhvxqq7vpWMtSX1T5rkHTkVY0GpVnKyLMfspB1BrG2PHPa6UOGRq 0/Tg+9wUVkjzLClZzmqQHE2/Rm8ylvNM7kc9H3ZblswnyT1ptLg7S5fnJUCzga6J1L c4bl4L66G919VRmQdX7AnLetjMW4QdnsIAVleDCU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732412AbgI2MhC (ORCPT ); Tue, 29 Sep 2020 08:37:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:35520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729504AbgI2LU6 (ORCPT ); Tue, 29 Sep 2020 07:20:58 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B82FE235F7; Tue, 29 Sep 2020 11:18:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601378310; bh=YlTmgV/qZt3ZFXhDb+TKIjKiP4FvzssjohG7yDlhUtw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jbCAWy7Hnz3ZAEpGUWEMXGoMTZtm3ylIjhRGgDdBp7gsfjS6yrwVkiV7SXWx6RnmF sWGVFYuIDYrGKZzCk6Mog5sE/2+N5uBDvtkDco+hoyDx9s1EVQXHGqNnr/d/iJxave wS3HD+BEQXL+AtT2gEvH9qkLNbw3jI6yxC90n8cE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Qian Cai , Daniel Wagner , Cornelia Huck , Alex Williamson , Sasha Levin Subject: [PATCH 4.14 136/166] vfio/pci: Clear error and request eventfd ctx after releasing Date: Tue, 29 Sep 2020 13:00:48 +0200 Message-Id: <20200929105941.993327048@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105935.184737111@linuxfoundation.org> References: <20200929105935.184737111@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alex Williamson [ Upstream commit 5c5866c593bbd444d0339ede6a8fb5f14ff66d72 ] The next use of the device will generate an underflow from the stale reference. Cc: Qian Cai Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx") Reported-by: Daniel Wagner Reviewed-by: Cornelia Huck Tested-by: Daniel Wagner Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/pci/vfio_pci.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 902854a013521..4fbc38b955ad8 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -399,10 +399,14 @@ static void vfio_pci_release(void *device_data) if (!(--vdev->refcnt)) { vfio_spapr_pci_eeh_release(vdev->pdev); vfio_pci_disable(vdev); - if (vdev->err_trigger) + if (vdev->err_trigger) { eventfd_ctx_put(vdev->err_trigger); - if (vdev->req_trigger) + vdev->err_trigger = NULL; + } + if (vdev->req_trigger) { eventfd_ctx_put(vdev->req_trigger); + vdev->req_trigger = NULL; + } } mutex_unlock(&driver_lock);