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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 103C0C433FF for ; Mon, 5 Aug 2019 13:06:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C45CF206C1 for ; Mon, 5 Aug 2019 13:06:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565010365; bh=T3yUBOYGKMU/N3Fg7zdm+pGfbdwpGg75Fm5Tr0WeYSc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=F4O7JnD7h86Wyu+VrYEJlt5zelO4jU4+AgrkhUO3ULBG4SI8SF9kSiLaJ/IHWirHH T3C+PNT/CPAkoMMDXi9PQvlXbE3d6CT2dWjY4SGhroLhzvaO8JqrcGUJCoKaxT8Zm8 ic0mzmKhh30gMhmn1h4jxMNUh6/SCusMvfEAPEJI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729470AbfHENGE (ORCPT ); Mon, 5 Aug 2019 09:06:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:42374 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728984AbfHENGC (ORCPT ); Mon, 5 Aug 2019 09:06:02 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 F07FB2147A; Mon, 5 Aug 2019 13:06:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565010361; bh=T3yUBOYGKMU/N3Fg7zdm+pGfbdwpGg75Fm5Tr0WeYSc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bHMr/PxAYk9T4nxOlHma1qSPuxIdHA87/QS8uPdo7oInumypLYbLbhPYPo8tp0gwQ 48Ylg8E/SuvMn73sNjw3cyWf04K1uf952S4rwynvtq6yjOyGTZbWdqBo596e74jDUS xyDyOUpFa455LGfsccdbHKNaLvU0hEPQXcD7nW3k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ajay Kaher , Jason Gunthorpe Subject: [PATCH 4.9 36/42] infiniband: fix race condition between infiniband mlx4, mlx5 driver and core dumping Date: Mon, 5 Aug 2019 15:03:02 +0200 Message-Id: <20190805124929.227277266@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190805124924.788666484@linuxfoundation.org> References: <20190805124924.788666484@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ajay Kaher This patch is the extension of following upstream commit to fix the race condition between get_task_mm() and core dumping for IB->mlx4 and IB->mlx5 drivers: commit 04f5866e41fb ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping")' Thanks to Jason for pointing this. Signed-off-by: Ajay Kaher Reviewed-by: Jason Gunthorpe Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/mlx4/main.c | 4 +++- drivers/infiniband/hw/mlx5/main.c | 3 +++ 2 files changed, 6 insertions(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -1172,6 +1172,8 @@ static void mlx4_ib_disassociate_ucontex * mlx4_ib_vma_close(). */ down_write(&owning_mm->mmap_sem); + if (!mmget_still_valid(owning_mm)) + goto skip_mm; for (i = 0; i < HW_BAR_COUNT; i++) { vma = context->hw_bar_info[i].vma; if (!vma) @@ -1190,7 +1192,7 @@ static void mlx4_ib_disassociate_ucontex /* context going to be destroyed, should not access ops any more */ context->hw_bar_info[i].vma->vm_ops = NULL; } - +skip_mm: up_write(&owning_mm->mmap_sem); mmput(owning_mm); put_task_struct(owning_process); --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1307,6 +1307,8 @@ static void mlx5_ib_disassociate_ucontex * mlx5_ib_vma_close. */ down_write(&owning_mm->mmap_sem); + if (!mmget_still_valid(owning_mm)) + goto skip_mm; list_for_each_entry_safe(vma_private, n, &context->vma_private_list, list) { vma = vma_private->vma; @@ -1321,6 +1323,7 @@ static void mlx5_ib_disassociate_ucontex list_del(&vma_private->list); kfree(vma_private); } +skip_mm: up_write(&owning_mm->mmap_sem); mmput(owning_mm); put_task_struct(owning_process);