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 0C991C25B08 for ; Wed, 10 Aug 2022 12:55:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232303AbiHJMzV (ORCPT ); Wed, 10 Aug 2022 08:55:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232283AbiHJMzQ (ORCPT ); Wed, 10 Aug 2022 08:55:16 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BF4317E0F; Wed, 10 Aug 2022 05:55:15 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id a8so14637973pjg.5; Wed, 10 Aug 2022 05:55:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to:from :subject:cc:to:message-id:date:from:to:cc; bh=q5pzR9cYI26uHb2cy0Dx2bZk76nwKD6XUexNgn2JD3g=; b=aCpqMOCjzmlO9Q+T6z3yMZv6hE5ss39fR7nIWjwLtApQs8ZD7SXYe5jCCot/gwAFKx VSzitsyCRP2TSw999TCe69gY3X9srVC+cPxa8eHBh8990A9A7PcgggnGLvIrTQJSRhyR ujF+6KJgfJILAW1b950XTL8kuAH9wJdgTwe3tvT6tNruN1PSPtQ2fMTm9NdK/ob5KHx8 uAkqZiPatMfO+YI2+PAjivtIZQ2XzCb/ZvSS4g6o0dGnfGuzKU+7XM23xt1sKEwt2FU+ Gs66XoJvPLd5nUDUqagBQJnQHduWQ6sgFt1NiISf+B30/A7v4QedA1Ayw1pqg/H2Ji0l PK5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to:from :subject:cc:to:message-id:date:x-gm-message-state:from:to:cc; bh=q5pzR9cYI26uHb2cy0Dx2bZk76nwKD6XUexNgn2JD3g=; b=1Gs4e1W7s7IWpX3llRtWoLVJ0fg/NacqmJFPcPe26UAHNKmE6wWfBclElWSJnX0+Zr CSVPYi+/gFrBcSPnxR12LkCn04ZSssjlibL4zX2p1UyBKFC2fA3GXWSmqPjWU/sJS+3h tanGRz+K+KhvRlRMbWicKTQtP94UyOIl+DWhOvd47hZ4VTA9hrYyvO1KByTMQZbt/LQe 4DBmzKBI6gg2LYWJ79kyr5wYDp8740S7rgK9UCGZbpcjQ+gD6srtYuvDWd8JOZs9iOMv pQ2RQ9R1fJ2v4OKAyLCvwuinRM6kgoHSjqPpCGpUk5erxt8QrRZ1z9Cez/K2A6Q745Zt eSng== X-Gm-Message-State: ACgBeo0kDwVI+/RLXq2c97cCE2bhAlNctqROC6YU6bF094ILQjWM6+lF 24tk3Y3iEXs07Dv0GeFtiw== X-Google-Smtp-Source: AA6agR6XFPySjhsoFztTXrEROd+fI8QbhtrR8lGEm8TdR23Z6SzvCV3ZyaBCtdaOCqEDRmUViVGb3A== X-Received: by 2002:a17:90b:1e0c:b0:1f5:4e52:4866 with SMTP id pg12-20020a17090b1e0c00b001f54e524866mr3679074pjb.230.1660136115053; Wed, 10 Aug 2022 05:55:15 -0700 (PDT) Received: from localhost ([240d:1a:c0d:9f00:4f2f:926a:23dd:8588]) by smtp.gmail.com with ESMTPSA id 7-20020a620407000000b0052d3e81886fsm1908364pfe.42.2022.08.10.05.55.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Aug 2022 05:55:14 -0700 (PDT) Date: Wed, 10 Aug 2022 21:55:10 +0900 (JST) Message-Id: <20220810.215510.73630597636704879.shigeru.yoshida@gmail.com> To: mst@redhat.com Cc: jasowang@redhat.com, axboe@kernel.dk, pbonzini@redhat.com, stefanha@redhat.com, virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] virtio-blk: Avoid use-after-free on suspend/resume From: Shigeru Yoshida In-Reply-To: <20220810084053-mutt-send-email-mst@kernel.org> References: <20220731070951.196831-1-shigeru.yoshida@gmail.com> <20220810.204556.441522765735488771.shigeru.yoshida@gmail.com> <20220810084053-mutt-send-email-mst@kernel.org> X-Mailer: Mew version 6.8 on Emacs 28.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, 10 Aug 2022 08:41:04 -0400, Michael S. Tsirkin wrote: > On Wed, Aug 10, 2022 at 08:45:56PM +0900, Shigeru Yoshida wrote: >> ping? >> >> On Sun, 31 Jul 2022 16:09:51 +0900, Shigeru Yoshida wrote: >> > hctx->user_data is set to vq in virtblk_init_hctx(). However, vq is >> > freed on suspend and reallocated on resume. So, hctx->user_data is >> > invalid after resume, and it will cause use-after-free accessing which >> > will result in the kernel crash something like below: >> > >> > [ 22.428391] Call Trace: >> > [ 22.428899] >> > [ 22.429339] virtqueue_add_split+0x3eb/0x620 >> > [ 22.430035] ? __blk_mq_alloc_requests+0x17f/0x2d0 >> > [ 22.430789] ? kvm_clock_get_cycles+0x14/0x30 >> > [ 22.431496] virtqueue_add_sgs+0xad/0xd0 >> > [ 22.432108] virtblk_add_req+0xe8/0x150 >> > [ 22.432692] virtio_queue_rqs+0xeb/0x210 >> > [ 22.433330] blk_mq_flush_plug_list+0x1b8/0x280 >> > [ 22.434059] __blk_flush_plug+0xe1/0x140 >> > [ 22.434853] blk_finish_plug+0x20/0x40 >> > [ 22.435512] read_pages+0x20a/0x2e0 >> > [ 22.436063] ? folio_add_lru+0x62/0xa0 >> > [ 22.436652] page_cache_ra_unbounded+0x112/0x160 >> > [ 22.437365] filemap_get_pages+0xe1/0x5b0 >> > [ 22.437964] ? context_to_sid+0x70/0x100 >> > [ 22.438580] ? sidtab_context_to_sid+0x32/0x400 >> > [ 22.439979] filemap_read+0xcd/0x3d0 >> > [ 22.440917] xfs_file_buffered_read+0x4a/0xc0 >> > [ 22.441984] xfs_file_read_iter+0x65/0xd0 >> > [ 22.442970] __kernel_read+0x160/0x2e0 >> > [ 22.443921] bprm_execve+0x21b/0x640 >> > [ 22.444809] do_execveat_common.isra.0+0x1a8/0x220 >> > [ 22.446008] __x64_sys_execve+0x2d/0x40 >> > [ 22.446920] do_syscall_64+0x37/0x90 >> > [ 22.447773] entry_SYSCALL_64_after_hwframe+0x63/0xcd >> > >> > This patch fixes this issue by getting vq from vblk, and removes >> > virtblk_init_hctx(). >> > >> > Signed-off-by: Shigeru Yoshida > > Fixes: 4e0400525691 ("virtio-blk: support polling I/O") > Cc: "Suwan Kim" > > I assume? Yes, this patch fixes the commit you mentioned. Thanks, Shigeru > >> > --- >> > drivers/block/virtio_blk.c | 24 ++++++++++-------------- >> > 1 file changed, 10 insertions(+), 14 deletions(-) >> > >> > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c >> > index 6fc7850c2b0a..d756423e0059 100644 >> > --- a/drivers/block/virtio_blk.c >> > +++ b/drivers/block/virtio_blk.c >> > @@ -101,6 +101,14 @@ static inline blk_status_t virtblk_result(struct virtblk_req *vbr) >> > } >> > } >> > >> > +static inline struct virtio_blk_vq *get_virtio_blk_vq(struct blk_mq_hw_ctx *hctx) >> > +{ >> > + struct virtio_blk *vblk = hctx->queue->queuedata; >> > + struct virtio_blk_vq *vq = &vblk->vqs[hctx->queue_num]; >> > + >> > + return vq; >> > +} >> > + >> > static int virtblk_add_req(struct virtqueue *vq, struct virtblk_req *vbr) >> > { >> > struct scatterlist hdr, status, *sgs[3]; >> > @@ -416,7 +424,7 @@ static void virtio_queue_rqs(struct request **rqlist) >> > struct request *requeue_list = NULL; >> > >> > rq_list_for_each_safe(rqlist, req, next) { >> > - struct virtio_blk_vq *vq = req->mq_hctx->driver_data; >> > + struct virtio_blk_vq *vq = get_virtio_blk_vq(req->mq_hctx); >> > bool kick; >> > >> > if (!virtblk_prep_rq_batch(req)) { >> > @@ -837,7 +845,7 @@ static void virtblk_complete_batch(struct io_comp_batch *iob) >> > static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) >> > { >> > struct virtio_blk *vblk = hctx->queue->queuedata; >> > - struct virtio_blk_vq *vq = hctx->driver_data; >> > + struct virtio_blk_vq *vq = get_virtio_blk_vq(hctx); >> > struct virtblk_req *vbr; >> > unsigned long flags; >> > unsigned int len; >> > @@ -862,22 +870,10 @@ static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob) >> > return found; >> > } >> > >> > -static int virtblk_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, >> > - unsigned int hctx_idx) >> > -{ >> > - struct virtio_blk *vblk = data; >> > - struct virtio_blk_vq *vq = &vblk->vqs[hctx_idx]; >> > - >> > - WARN_ON(vblk->tag_set.tags[hctx_idx] != hctx->tags); >> > - hctx->driver_data = vq; >> > - return 0; >> > -} >> > - >> > static const struct blk_mq_ops virtio_mq_ops = { >> > .queue_rq = virtio_queue_rq, >> > .queue_rqs = virtio_queue_rqs, >> > .commit_rqs = virtio_commit_rqs, >> > - .init_hctx = virtblk_init_hctx, >> > .complete = virtblk_request_done, >> > .map_queues = virtblk_map_queues, >> > .poll = virtblk_poll, >> > -- >> > 2.37.1 >> > >