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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE7ACC433F5 for ; Wed, 18 May 2022 21:36:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243227AbiERVgf (ORCPT ); Wed, 18 May 2022 17:36:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243226AbiERVge (ORCPT ); Wed, 18 May 2022 17:36:34 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D62341312B6 for ; Wed, 18 May 2022 14:36:32 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id qe3-20020a17090b4f8300b001dc24e4da73so4713085pjb.1 for ; Wed, 18 May 2022 14:36:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:content-language:to:from :subject:content-transfer-encoding; bh=GCrsoYoJogRw4suK6Mtl2SFfz8POK/GVn4txr+5xPAM=; b=A67y/eFMCiFRtcXbuLlQGXKgI8P3NBLyGlKTk5twtaYl1ZT3J96/oUuOojF9kL9ROV xLPBG/HQvUZIsDCvFPY6YV0gdOSJoU7CBVJIdiFEThRaUT9mvrkswD1Qorib7KPtC9+C xQp0VK+BMK/SXkfvE/PrAdz3mL1Dq8Nl7qPjp0T359jI3iMn0IYIlZh53CZvN4I1Yy+1 DkHtTbPSi+I1IDQZm/LRCDPes1mFxbH5xArbkvJB1emgNEUhLX4v3uxwiwFE/Zsp0Go/ b+hN59DJ0gabqIzk3/4m7X+6WaS7kIMTPgFxgfhz+LAFuYtjTgwE0Qpl8BxbtVFaxxQJ WSXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent :content-language:to:from:subject:content-transfer-encoding; bh=GCrsoYoJogRw4suK6Mtl2SFfz8POK/GVn4txr+5xPAM=; b=OlMFPpvvxLUC4LMtSTi+Lr8W1uaVDyRU2Qsd6uF4+PiNac+ns+QIG+owJsN6U/38yT UVYtIAobLyUQA5LANI6aq2xghlLHgskG5YN54RdxYg/Ngo+DWzz7exZWEnucMckEoJ+a TvD3R59XgsE8U7PVGfypAOiytRQSg0sQ73ev/k7vamG8Kpfb9ybpRHCXcx0NiMtOC8bk VjzVQKyHp/ITV1O81oPDgtpivFmwM5prfGvwPh6K/bPxREOW0yyAP76qmNlc0NDvetlf NTsuYsq4XAJ7oiepryUipDCF6wDhv3XJS+Ap3sbczCb6Nnh0D3ynElW4P4SBCaiF4Szv kCYw== X-Gm-Message-State: AOAM530+G7msb3UZ+aF71Xd3f7TVEHnwEp25Sz4+OvYIoKj938abrOdC Cb7e3FKSW/jxG0xgP9FyITU4fQ9V/lfC8g== X-Google-Smtp-Source: ABdhPJzLzXJ6mnSHd0RbY9qlClFWvLlqGvLomm3xwHxcMeoCwymbofh8/Bzb7kLALe9wLbXXiuvXHA== X-Received: by 2002:a17:90b:48d1:b0:1df:4fc8:c2d7 with SMTP id li17-20020a17090b48d100b001df4fc8c2d7mr1471685pjb.45.1652909792032; Wed, 18 May 2022 14:36:32 -0700 (PDT) Received: from ?IPV6:2600:380:7454:420e:4a75:de43:4286:5c17? ([2600:380:7454:420e:4a75:de43:4286:5c17]) by smtp.gmail.com with ESMTPSA id j7-20020a170902da8700b0015e8d4eb1ffsm2165853plx.73.2022.05.18.14.36.30 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 18 May 2022 14:36:31 -0700 (PDT) Message-ID: <8909354e-4fb2-8a71-cc22-6d8be092f835@kernel.dk> Date: Wed, 18 May 2022 15:36:29 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Content-Language: en-US To: io-uring From: Jens Axboe Subject: [PATCH] io_uring: disallow mixed provided buffer group registrations Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org It's nonsensical to register a provided buffer ring, if a classic provided buffer group with the same ID exists. Depending on the order of which we decide what type to pick, the other type will never get used. Explicitly disallow it and return an error if this is attempted. Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers") Signed-off-by: Jens Axboe --- diff --git a/fs/io_uring.c b/fs/io_uring.c index 24d56b2a0637..065ea45de29c 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -12156,9 +12156,11 @@ static int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) } bl = io_buffer_get_list(ctx, reg.bgid); - if (bl && bl->buf_nr_pages) - return -EEXIST; - if (!bl) { + if (bl) { + /* if mapped buffer ring OR classic exists, don't allow */ + if (bl->buf_nr_pages || !list_empty(&bl->buf_list)) + return -EEXIST; + } else { bl = kzalloc(sizeof(*bl), GFP_KERNEL); if (!bl) return -ENOMEM; -- Jens Axboe