From patchwork Sat Oct 31 11:35:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 317366 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=BAYES_00,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 76F51C388F9 for ; Sat, 31 Oct 2020 11:48:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 38A0720731 for ; Sat, 31 Oct 2020 11:48:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604144934; bh=7FOVsB7YlhInGJThELoraNZAldV/rJyW34BnP0y0MBQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RgkF/IvhNl6fQPgEdzAeScsMmLoZ0YL+YIqFSwFiisBG/0WZdf9HC+lPFqsJ5rQg2 vFXYbbMCRfK9fWUPJJc9MvOyaojOsIE02OzRM4/tQpz6CfWSko6Byr756Dp/8uDgR0 QEEGDLGuLfeC74rVQpoZHxTP+cxa2+A2hwv9vdZk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727647AbgJaLsx (ORCPT ); Sat, 31 Oct 2020 07:48:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:43504 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728014AbgJaLnb (ORCPT ); Sat, 31 Oct 2020 07:43:31 -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 18BBF205F4; Sat, 31 Oct 2020 11:43:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604144610; bh=7FOVsB7YlhInGJThELoraNZAldV/rJyW34BnP0y0MBQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hrJzAC4TKNYmr9mZ7zcYAePBTR25yCr5FRefwWGDbbJH8CaFILelGUByOfQwVN0hQ vhpBAijr4MN2oRmIMLLIHqiA/L43IjK4F0IvDi84ttObJO1o9W5GPdkKvSgDN9xnZ4 ogDp7WASsUY4OEeCFB2pllJU6tF2+w4J3xTpHJDg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+27c12725d8ff0bfe1a13@syzkaller.appspotmail.com, "Matthew Wilcox (Oracle)" , Jens Axboe Subject: [PATCH 5.9 14/74] io_uring: Fix use of XArray in __io_uring_files_cancel Date: Sat, 31 Oct 2020 12:35:56 +0100 Message-Id: <20201031113500.734482886@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201031113500.031279088@linuxfoundation.org> References: <20201031113500.031279088@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: "Matthew Wilcox (Oracle)" commit ce765372bc443573d1d339a2bf4995de385dea3a upstream. We have to drop the lock during each iteration, so there's no advantage to using the advanced API. Convert this to a standard xa_for_each() loop. Reported-by: syzbot+27c12725d8ff0bfe1a13@syzkaller.appspotmail.com Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- fs/io_uring.c | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-) --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -8415,28 +8415,19 @@ static void io_uring_attempt_task_drop(s void __io_uring_files_cancel(struct files_struct *files) { struct io_uring_task *tctx = current->io_uring; - XA_STATE(xas, &tctx->xa, 0); + struct file *file; + unsigned long index; /* make sure overflow events are dropped */ tctx->in_idle = true; - do { - struct io_ring_ctx *ctx; - struct file *file; - - xas_lock(&xas); - file = xas_next_entry(&xas, ULONG_MAX); - xas_unlock(&xas); - - if (!file) - break; - - ctx = file->private_data; + xa_for_each(&tctx->xa, index, file) { + struct io_ring_ctx *ctx = file->private_data; io_uring_cancel_task_requests(ctx, files); if (files) io_uring_del_task_file(file); - } while (1); + } } static inline bool io_uring_task_idle(struct io_uring_task *tctx)