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=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 52939C433B4 for ; Fri, 14 May 2021 00:43:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2ECEA61421 for ; Fri, 14 May 2021 00:43:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231159AbhENApC (ORCPT ); Thu, 13 May 2021 20:45:02 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:28538 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231826AbhENApC (ORCPT ); Thu, 13 May 2021 20:45:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620953031; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=fSpObU/MutR7JjIlPvkAIGgdfX9rUhAqm4YtXAKuWAw=; b=XnVBFuBci8FPO7H7388vE4QT1eHRUNRnjzy4xM4HoXvJ1NHwYVS+qzpRjDwDG1Qxry8WkA yxLEtKVc8NUoEtZmizKnSJALmbuKFfdPpnNDe0dI4pWf/MvpH7BlFJ0BADNu/jX8df4oZU bYRXYCMQKCW7xfabr3zIUB/m8lejRKk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-352-_4lbc2wFPxmVUBnbnPfouQ-1; Thu, 13 May 2021 20:43:47 -0400 X-MC-Unique: _4lbc2wFPxmVUBnbnPfouQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5E148107ACE3; Fri, 14 May 2021 00:43:46 +0000 (UTC) Received: from T590 (ovpn-12-87.pek2.redhat.com [10.72.12.87]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7EF955D9E3; Fri, 14 May 2021 00:43:39 +0000 (UTC) Date: Fri, 14 May 2021 08:43:34 +0800 From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Bart Van Assche , Hannes Reinecke , John Garry , Christoph Hellwig , David Jeffery , Shinichiro Kawasaki Subject: Re: [PATCH V7 0/4] blk-mq: fix request UAF related with iterating over tagset requests Message-ID: References: <20210511152236.763464-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210511152236.763464-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, May 11, 2021 at 11:22:32PM +0800, Ming Lei wrote: > Hi Jens, > > This patchset fixes the request UAF issue by one simple approach, > without clearing ->rqs[] in fast path, please consider it for 5.13. > > 1) grab request's ref before calling ->fn in blk_mq_tagset_busy_iter, > and release it after calling ->fn, so ->fn won't be called for one > request if its queue is frozen, done in 2st patch > > 2) clearing any stale request referred in ->rqs[] before freeing the > request pool, one per-tags spinlock is added for protecting > grabbing request ref vs. clearing ->rqs[tag], so UAF by refcount_inc_not_zero > in bt_tags_iter() is avoided, done in 3rd patch. > > V7: > - fix one null-ptr-deref during updating nr_hw_queues, because > blk_mq_clear_flush_rq_mapping() may touch non-mapped hw queue's > tags, only patch 4/4 is modified, reported and verified by > Shinichiro Kawasaki > - run blktests and not see regression Hi Jens, We have been working on this issue for a bit long, so any chance to get the fixes merged? Either 5.13 or 5.14 is fine. Thanks, Ming