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=-10.0 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=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 322B7C433DF for ; Mon, 10 Aug 2020 15:27:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03F5322BF3 for ; Mon, 10 Aug 2020 15:27:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073236; bh=qRI9lOsRho7/4Hw+5MD8A/vCTNs9jDyDvvANGYuj8Vo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hcGOlC717bJbMtj1U5KNEXu1i3iQiEosapYqz6EL8G7Yw3iO6J94AN7OUs7fUvyNS d54mZVJvW0EEmLTqCbUem1dVnnj/oEnMp9wwhN3jIljCHP03BuXiX9ZYdrQEAuiOeA PDZ6XIvLeDVg8GVjmlhqclIiPcPcqn5dpgZtsy9E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728712AbgHJP1O (ORCPT ); Mon, 10 Aug 2020 11:27:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:60928 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728683AbgHJP0w (ORCPT ); Mon, 10 Aug 2020 11:26:52 -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 EEE9322DD6; Mon, 10 Aug 2020 15:26:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073212; bh=qRI9lOsRho7/4Hw+5MD8A/vCTNs9jDyDvvANGYuj8Vo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uEuTFusteeMmxXN7CvG+eeRu8GJCO9Gp2qASOoP6Ii1PGmYW6PPsC/qjENwsSJdda CPVvxIcwKHUApISeg9ZCAA1TpBglAxqPW2I3TRlvDGpyxjgzpLYCzV43QGkP9NIsfK Yt1RWVWQLuFI2n3AV3KtXfpUP5K8a0TXWvpG+N1E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Guoyu Huang , Jens Axboe Subject: [PATCH 5.4 07/67] io_uring: Fix use-after-free in io_sq_wq_submit_work() Date: Mon, 10 Aug 2020 17:20:54 +0200 Message-Id: <20200810151809.797954399@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200810151809.438685785@linuxfoundation.org> References: <20200810151809.438685785@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: Guoyu Huang when ctx->sqo_mm is zero, io_sq_wq_submit_work() frees 'req' without deleting it from 'task_list'. After that, 'req' is accessed in io_ring_ctx_wait_and_kill() which lead to a use-after-free. Signed-off-by: Guoyu Huang Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- fs/io_uring.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2232,6 +2232,7 @@ restart: if (io_req_needs_user(req) && !cur_mm) { if (!mmget_not_zero(ctx->sqo_mm)) { ret = -EFAULT; + goto end_req; } else { cur_mm = ctx->sqo_mm; use_mm(cur_mm);