From patchwork Wed Aug 5 03:40:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guoyu Huang X-Patchwork-Id: 11701245 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0C67214DD for ; Wed, 5 Aug 2020 03:40:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E75F922B40 for ; Wed, 5 Aug 2020 03:40:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iY9JbyNS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726130AbgHEDkt (ORCPT ); Tue, 4 Aug 2020 23:40:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725904AbgHEDks (ORCPT ); Tue, 4 Aug 2020 23:40:48 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75F0EC06174A; Tue, 4 Aug 2020 20:40:48 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id m8so15048379pfh.3; Tue, 04 Aug 2020 20:40:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition; bh=rzzRqXjFEunIT1yZSSg1CKlJvEECBfp+MgDWsFWjUvI=; b=iY9JbyNSBtjDkkcBBtYVJi6/b9GolFcvDtU5KawfaZyA0+9dTCDa1AK05EKbNQITlD XTfONIbcJTPP3ZlXxb4BOXtL6LD1cZLatdjtewM/9xZyu7gJFP9niti9X8PGmvHJYE64 iXQCVANYc8YQwGDsJ+JxDHMKno8uNzqF/czmj2ldHbVJ5aXtDjugL+Z+QkoIlcS9X0xq eZi8mAl5v78paw8vu84acHnxcbZ+nIiFJZ8khS7u56z0GW6mN5Zpxv4fhZJ1fVqX5OVD q/XxF4V7t825zQNceionDeEusM3nNlgIB3dlA/JeDXfRMIkVUrClZTIjBV6NOUWRHJ0x b5vQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition; bh=rzzRqXjFEunIT1yZSSg1CKlJvEECBfp+MgDWsFWjUvI=; b=jNy8FOZoQUWBjJmJc5T/4TZ+ccfovBxWiQFhDA5NpEVAZ22ShJa/AYhkekrJbYKa4p M8R/ujcDobwBWertH4YsZsbrC7LxtD5wxJ3sSdsmU1DdDy8mlb+oNfc6KGeNCh3xv8Ul AoqabSqRf7RMcr1qcRv3/zvIN1tosZZ2iwj4HBD28TcaKBpRI3SfgN872cKk5WZ8V57K QuwuTWzPR6N/nsqoMJXJn4B8LSDjjSG9JSUvI2V0XH8XwhbEFKFUBWhdRJXIwZKXDeUd Sirl2DDAY+vh2g35Fc21YPIv5IdHbhedn6+JYySefxeTPpeI9G8p/0CPdUU6/4Diw7lW s3AA== X-Gm-Message-State: AOAM530e/CWrEsgAxlW4dAFTK3Rn9Vf93tTSpeFH/iFykv++SZO+aEd1 S+9Ixv3WD1LpNJh9FUjUqNO7+VF0ned95w== X-Google-Smtp-Source: ABdhPJx1HdDmTQsmnl2GToZoJYpx9vzI2MF9PZc28RwIEtemGRYvTPfbA+FHPNR1D3IEHrHbsCiJ5A== X-Received: by 2002:aa7:810c:: with SMTP id b12mr1449191pfi.69.1596598847760; Tue, 04 Aug 2020 20:40:47 -0700 (PDT) Received: from localhost ([104.192.108.9]) by smtp.gmail.com with ESMTPSA id fh14sm810632pjb.38.2020.08.04.20.40.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Aug 2020 20:40:47 -0700 (PDT) Date: Tue, 4 Aug 2020 20:40:42 -0700 From: Guoyu Huang To: axboe@kernel.dk, viro@zeniv.linux.org.uk Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] io_uring: Fix use-after-free in io_sq_wq_submit_work() Message-ID: <20200805034042.GA29805@ubuntu> MIME-Version: 1.0 Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org 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 --- fs/io_uring.c | 1 + 1 file changed, 1 insertion(+) -- 2.25.1 diff --git a/fs/io_uring.c b/fs/io_uring.c index e0200406765c..4b5ac381c67f 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2242,6 +2242,7 @@ static void io_sq_wq_submit_work(struct work_struct *work) if (io_sqe_needs_user(sqe) && !cur_mm) { if (!mmget_not_zero(ctx->sqo_mm)) { ret = -EFAULT; + goto end_req; } else { cur_mm = ctx->sqo_mm; use_mm(cur_mm);