From patchwork Tue Sep 29 11:00:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 291108 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 5BE41C4727F for ; Tue, 29 Sep 2020 11:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1878620702 for ; Tue, 29 Sep 2020 11:42:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601379770; bh=yGyQvtcrzzOsuLns5qoWHAXVBcKYt/j9EFNRVIfjoHU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=K2RFyZ/Dao3zfcn6QkvfNWlssFXM0oH/lDis0o5ejvUdb78giXHPdbtroiAogBBaJ Iih4TfdppIoQg64+P5IS1jJwZ0JxYGshWvVAA8MTM6sX9qRfyCIExVZ1xx9QVbPF7v Cf0TXtumpn87dczJ73yPtYlGWaP9rLwFYE00GSBA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730731AbgI2Lmn (ORCPT ); Tue, 29 Sep 2020 07:42:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:40210 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730470AbgI2Lmf (ORCPT ); Tue, 29 Sep 2020 07:42:35 -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 3BE7520702; Tue, 29 Sep 2020 11:42:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601379754; bh=yGyQvtcrzzOsuLns5qoWHAXVBcKYt/j9EFNRVIfjoHU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Vb1IUDodbXAeTZHTsoP+fDWXiHoDijxKaHpBwHnQV+nJDf8jxfJT9CkxXRtIuFoFs 1xL+2sNZJl6E6oHZF/rverkWCfaXHRAUD8nA+fKWMF64SnPNyk6oiGW5Wt8nDAh2Jp Ei3VFD/DtpHxHHKanwcbfziNasfihYyKNJOm8l2A= 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 5.4 303/388] vfio/pci: Clear error and request eventfd ctx after releasing Date: Tue, 29 Sep 2020 13:00:34 +0200 Message-Id: <20200929110025.132412620@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929110010.467764689@linuxfoundation.org> References: <20200929110010.467764689@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 12f7691e8b6ca..b669be5a20066 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -474,10 +474,14 @@ 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(&vdev->reflck->lock);