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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 C1851C3B19F for ; Fri, 14 Feb 2020 15:59:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8FC5524654 for ; Fri, 14 Feb 2020 15:59:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581695948; bh=PLNrytnzgF1eAeTHEjvYL517Oe7v9++dJm1YPKnNc2U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2dt9QTWoCr2ZxcETtsztAZM+dieDnal/8eiShwhEhHt8/B59WJI9LbM/Ls3yeJLeB mQIwZF7x1DNmrDPIX6xrvWEQgX61n+h3M1vwmEWEpas4Vmo5kcFG9G0RTkJKOzj/hK ym+IRyO6EjjF/Q05DDDyZeoV5RTnN1YOT0771/TA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388133AbgBNP7I (ORCPT ); Fri, 14 Feb 2020 10:59:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:43300 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388400AbgBNP6y (ORCPT ); Fri, 14 Feb 2020 10:58:54 -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 5FF04222C4; Fri, 14 Feb 2020 15:58:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581695934; bh=PLNrytnzgF1eAeTHEjvYL517Oe7v9++dJm1YPKnNc2U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S5lqIXlvgeFHkmc3ms1vvR9ZrOlliLaSHMZt8hbDRq5o8Su/Pi0Cdn4lWnBQkG6+y 6CtaL4hC4eQCuHTIbvlRi8zqerUp/CsRZPuOY3eQ3d9XvVumnUw1TTliU7600UaHab 8Eb03El6glPRq30+Ig9+gJoii2/YFwTW73hCL+yg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jason Gunthorpe , Gal Pressman , Michal Kalderon , Sasha Levin , linux-rdma@vger.kernel.org Subject: [PATCH AUTOSEL 5.5 469/542] RDMA/core: Ensure that rdma_user_mmap_entry_remove() is a fence Date: Fri, 14 Feb 2020 10:47:41 -0500 Message-Id: <20200214154854.6746-469-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214154854.6746-1-sashal@kernel.org> References: <20200214154854.6746-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jason Gunthorpe [ Upstream commit 6b3712c0246ca7b2b8fa05eab2362cf267410f7e ] The set of entry->driver_removed is missing locking, protect it with xa_lock() which is held by the only reader. Otherwise readers may continue to see driver_removed = false after rdma_user_mmap_entry_remove() returns and may continue to try and establish new mmaps. Fixes: 3411f9f01b76 ("RDMA/core: Create mmap database and cookie helper functions") Link: https://lore.kernel.org/r/20200115202041.GA17199@ziepe.ca Reviewed-by: Gal Pressman Acked-by: Michal Kalderon Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/core/ib_core_uverbs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/core/ib_core_uverbs.c b/drivers/infiniband/core/ib_core_uverbs.c index b7cb59844ece4..b51bd7087a881 100644 --- a/drivers/infiniband/core/ib_core_uverbs.c +++ b/drivers/infiniband/core/ib_core_uverbs.c @@ -232,7 +232,9 @@ void rdma_user_mmap_entry_remove(struct rdma_user_mmap_entry *entry) if (!entry) return; + xa_lock(&entry->ucontext->mmap_xa); entry->driver_removed = true; + xa_unlock(&entry->ucontext->mmap_xa); kref_put(&entry->ref, rdma_user_mmap_entry_free); } EXPORT_SYMBOL(rdma_user_mmap_entry_remove); -- 2.20.1