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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,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 B15F2C433E1 for ; Tue, 18 Aug 2020 12:06:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8188120786 for ; Tue, 18 Aug 2020 12:06:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597752368; bh=ZtbGxd5ePE3ZfpfKfEvHXxhqorpfEQaB2XcZXm4UfsA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fyTDI0mJzoeQpKoGIsB+TGgn0+jlAy75MDh/8UnNwIHeD8P8VjwfcmwTsQ4uPHODy KAYWpRVYTDMbhvNrFamk5W6a/9xLkp4NexW9QoKebLO67QcGL827ASK9B5Xc7hiQAP QaSRAg8gGbZHntfgRuq7cGfLXXje6Ig6ZpKdQcGc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726585AbgHRMGH (ORCPT ); Tue, 18 Aug 2020 08:06:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:32956 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726480AbgHRMGF (ORCPT ); Tue, 18 Aug 2020 08:06:05 -0400 Received: from localhost (unknown [213.57.247.131]) (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 56F0B204EA; Tue, 18 Aug 2020 12:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597752365; bh=ZtbGxd5ePE3ZfpfKfEvHXxhqorpfEQaB2XcZXm4UfsA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NGdrXRoly+HaD4saK3YkOGybQlsH7MX8C0Mwf7RfxY1EMqqaYh510q+SJFJR8Dxk2 XQsqZopAJNbVYKI0g4BBT6P66neu5P60o5r/uE3x3+Qi28UubZVh3Cm0uHWP8JO2fb Hw5Hu9aLCTRZlfO95rMeTux5YuViX6E/jKDvD8gQ= From: Leon Romanovsky To: Doug Ledford , Jason Gunthorpe Cc: Leon Romanovsky , linux-rdma@vger.kernel.org, Roland Dreier , Sean Hefty Subject: [PATCH rdma-next 09/14] RDMA/ucma: Fix locking for ctx->events_reported Date: Tue, 18 Aug 2020 15:05:21 +0300 Message-Id: <20200818120526.702120-10-leon@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200818120526.702120-1-leon@kernel.org> References: <20200818120526.702120-1-leon@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: Jason Gunthorpe This value is locked under the file->mut, ensure it is held whenever touching it. The case in ucma_migrate_id() is a race, while in ucma_free_uctx() it is already not possible for the write side to run, the movement is just for clarity. Fixes: 88314e4dda1e ("RDMA/cma: add support for rdma_migrate_id()") Signed-off-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky --- drivers/infiniband/core/ucma.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index f7ec71225e87..ca5c44cac48c 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -587,6 +587,7 @@ static int ucma_free_ctx(struct ucma_context *ctx) list_move_tail(&uevent->list, &list); } list_del(&ctx->list); + events_reported = ctx->events_reported; mutex_unlock(&ctx->file->mut); list_for_each_entry_safe(uevent, tmp, &list, list) { @@ -596,7 +597,6 @@ static int ucma_free_ctx(struct ucma_context *ctx) kfree(uevent); } - events_reported = ctx->events_reported; mutex_destroy(&ctx->mutex); kfree(ctx); return events_reported; @@ -1697,7 +1697,9 @@ static ssize_t ucma_migrate_id(struct ucma_file *new_file, rdma_lock_handler(ctx->cm_id); cur_file = ctx->file; if (cur_file == new_file) { + mutex_lock(&cur_file->mut); resp.events_reported = ctx->events_reported; + mutex_unlock(&cur_file->mut); goto response; } -- 2.26.2