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=-14.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 0B166C43460 for ; Thu, 29 Apr 2021 11:45:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7ECD6144E for ; Thu, 29 Apr 2021 11:45:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233620AbhD2Lp5 (ORCPT ); Thu, 29 Apr 2021 07:45:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60418 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230148AbhD2Lpz (ORCPT ); Thu, 29 Apr 2021 07:45:55 -0400 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE127C06138B; Thu, 29 Apr 2021 04:45:07 -0700 (PDT) Received: by mail-wm1-x32a.google.com with SMTP id 82-20020a1c01550000b0290142562ff7c9so6503311wmb.3; Thu, 29 Apr 2021 04:45:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=F/E93CRR5FQ463ng5fsR0yJfZQcAbVR1kzGbCsVjcsM=; b=sI9Ui8m9o3qQiQBmaDpT7Kbk4HWncskcTosi2V1YtnxOxHoEhYll9gRZvSTKT/FXdX XeiFUu8W2qRNW6IwrOSstna5nTK0/E8+YDtAxIvEtdemwkg40Inx+QGOuXI82k1ObEx3 +XaxuZEofDivKU4QMDj+o8q9ij+PTdbN+5q0INwOx+W6kGN5zzHIYhLH8IalyGg7Slwv QuJh4RDpopDoEXjmLmtzzaTnSwj0zXkjw9sPHB0ALS1Y0wRYNFxx2GOxuFpLmfg7PsJ1 DZrDGjPRdPctUsqMHrRM/9JeRS8km5kAm8Vnvo1Tk/Dh4xiw8AYBNTBqgNOoOs9DPiBh 9jUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=F/E93CRR5FQ463ng5fsR0yJfZQcAbVR1kzGbCsVjcsM=; b=EF/0JwEUblDfDuwUjQMJSl0qjguwEXJdJP1jA1Qs1D0bQe649e0myOtJOKVErhk1pu VPckbtW/e6bYRhgjSAqH2xEJqEGnydVLBuBQnMeZHTZ08ZPal6K6VpiPpKl85b9u7cSY DK+9xIdaxk6ms5ZFHGqLQPRIO3lppdIYB8CJYmv1RZKhwaxpL1ymgM/39irpXGTk/R9e fnRfEaR9xFhLOThOVLOiTADoS0jnJpuvUmqNsY1AgmFb6qZ6ZTueXoRTOePEaAx6uCbO pSQsj3zR54sqR6bmcYihGaSNCwdgfPI5lfUFf8k8Xw3qFdzVw4khabL8Jv2q2hn6CVU2 qf1g== X-Gm-Message-State: AOAM530WlLus1HFvKm833bn21hWdQYp5H5OsUxjsCCxkQz8CqfyrwTDA vDy4nqv4pGP+MHtKJD+kvt4qHNQWfHE= X-Google-Smtp-Source: ABdhPJxyaXwzqJgFghBRmR1lYh/G//aPzgSelniw6V8gNedEaFZTuBR2679knDVqnMNPUSZBJYYR2A== X-Received: by 2002:a05:600c:35cc:: with SMTP id r12mr9991089wmq.147.1619696706253; Thu, 29 Apr 2021 04:45:06 -0700 (PDT) Received: from [192.168.8.197] ([148.252.132.80]) by smtp.gmail.com with ESMTPSA id k15sm4379209wro.87.2021.04.29.04.45.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 29 Apr 2021 04:45:05 -0700 (PDT) Subject: Re: [PATCH][next][V2] io_uring: Fix premature return from loop and memory leak To: Colin King , Jens Axboe , io-uring@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210429104602.62676-1-colin.king@canonical.com> From: Pavel Begunkov Message-ID: <5c8db42c-3b5c-be23-1c4e-f7438fe02e54@gmail.com> Date: Thu, 29 Apr 2021 12:45:01 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: <20210429104602.62676-1-colin.king@canonical.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/29/21 11:46 AM, Colin King wrote: > From: Colin Ian King > > Currently the -EINVAL error return path is leaking memory allocated > to data. Fix this by not returning immediately but instead setting > the error return variable to -EINVAL and breaking out of the loop. > > Kudos to Pavel Begunkov for suggesting a correct fix. Looks good, thanks Reviewed-by: Pavel Begunkov > > Signed-off-by: Colin Ian King > --- > > V2: set ret/err to -EINVAL and break rather than kfree and return, > fix both occurrences of this issue. > > --- > fs/io_uring.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index 47c2f126f885..c783ad83f220 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -8417,8 +8417,10 @@ static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, > ret = io_buffer_validate(&iov); > if (ret) > break; > - if (!iov.iov_base && tag) > - return -EINVAL; > + if (!iov.iov_base && tag) { > + ret = -EINVAL; > + break; > + } > > ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], > &last_hpage); > @@ -8468,8 +8470,10 @@ static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, > err = io_buffer_validate(&iov); > if (err) > break; > - if (!iov.iov_base && tag) > - return -EINVAL; > + if (!iov.iov_base && tag) { > + err = -EINVAL; > + break; > + } > err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); > if (err) > break; > -- Pavel Begunkov