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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 DAFBEC433E1 for ; Mon, 18 May 2020 18:02:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5279208A9 for ; Mon, 18 May 2020 18:02:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589824960; bh=SzXkSbZLavbpySA8SPOGSVH6HZgXsI0Fz963gWwXshQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IAzuLt/iGQ9nPCOw1Abx+0HI0fubHiNSw+HCqlG2jKc/9GIMtnmwp8mVG9/pYlYLS uF1YMsznMHEVANOCeMgNVxtT+gO1bSTQBn/q9KDPJ7RhVdj/Ox0y2nYMUU3aCxBor1 +afQlJHUfVJAVm4uoT9L43B1xFpu98Y0Gg0kQVAU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731732AbgERSCg (ORCPT ); Mon, 18 May 2020 14:02:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:46744 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732537AbgERSCc (ORCPT ); Mon, 18 May 2020 14:02:32 -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 4318B21582; Mon, 18 May 2020 18:02:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589824951; bh=SzXkSbZLavbpySA8SPOGSVH6HZgXsI0Fz963gWwXshQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YBljnOdtdmZJKm1Eq9ZcTvA+LKYVT8Cb+/PZVjWMy9M9XfVUUMpzkUqg+yaQTbj/U 5o5iYdcAA2dioY/gotZYAXF1NRWiE3OS1gQCtkk13xKie9TPMh/V5YNLXv7/DHUXaX UF9V9Ro7bgZl1tv8FnnsVGKjAFamZaVh1OKKN/Fc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Begunkov , Jens Axboe , Sasha Levin Subject: [PATCH 5.6 068/194] io_uring: check non-sync defer_list carefully Date: Mon, 18 May 2020 19:35:58 +0200 Message-Id: <20200518173537.403295842@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173531.455604187@linuxfoundation.org> References: <20200518173531.455604187@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Pavel Begunkov [ Upstream commit 4ee3631451c9a62e6b6bc7ee51fb9a5b34e33509 ] io_req_defer() do double-checked locking. Use proper helpers for that, i.e. list_empty_careful(). Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 01f71b9efb88f..832e042531bc4 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4258,7 +4258,7 @@ static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) int ret; /* Still need defer if there is pending req in defer list. */ - if (!req_need_defer(req) && list_empty(&ctx->defer_list)) + if (!req_need_defer(req) && list_empty_careful(&ctx->defer_list)) return 0; if (!req->io && io_alloc_async_ctx(req)) -- 2.20.1