Received: by 2002:a25:7ec1:0:0:0:0:0 with SMTP id z184csp3373742ybc; Mon, 25 Nov 2019 13:25:39 -0800 (PST) X-Google-Smtp-Source: APXvYqy/usQlUbQpBcrZELL4+33bMEbOf3MRwCPqUnAwsd7EzqCMlR+8oyqscGxzVDcUUe68VxNh X-Received: by 2002:a17:906:5959:: with SMTP id g25mr38613867ejr.248.1574717139576; Mon, 25 Nov 2019 13:25:39 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1574717139; cv=none; d=google.com; s=arc-20160816; b=KDS5oeJctiDZ9DwU2Jnv/ysOXSGkIYvC1XvJ1Rh76krnC6Z7IKYVLmPeds09pfMNtu mPL8jDn3g1x3l10pLSeixS0Vm+U1uuOzzrvIDm+XgoHwdEOfk6AMnQPy1m/PcHPXSU5U jxGZ7IwX0iLfZSxK7gOwOmbkvke2dQWnS7KEM1ld7Cjv8AhGySD8h7bURwm/T1L8FoLc IaFc4cn46Potxi0idCPfHhNXuPv7fkO9q/opcDxLztgI97P2M8Ofs8WyMEFmOLJl+jKY BitJvdgt1ryBP4fn9HhT1Q4OFwWs/MRdeW3KicdN3MSeVEODAY0Ea3pvXVg4BXQOkFOx SnMg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:message-id:in-reply-to :subject:cc:to:from:date; bh=g6+PZ7jcDnZMN/gbUnnfB4CoyEixYyRfEnly+X+AOsI=; b=jQGLqac187PIQp17fUbE5TQdSfOqjc5aok8rSTzJqSLpLKNnmst0mSWkV8BW/aATz2 XJBYnYIyZZ9MR8QJC1L90QofWCVvGGAhj9wU4Xpr2HF1r5rt0c0//x6R8t5fE1rQIGI5 AXCNQ44+a9wzKaSJ/hRClUjs1ALPqTLxlcJV6sp+WDt+R8Qlg8Aug+9sIIxmy2jbt1Tf oKHvaFCfh+RxizgZ/Khptr0ezswrEkOGA4qL0VSkrV/tTAkzVePg57mbziTggDNsLQzB yUIFf9DDzYwNRI0hwXruK/mItbgRrCJWUSMcDtMCo5pgXbhhKtDReZXwS4mMWNkigMb+ NBjQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id y24si5416009ejc.170.2019.11.25.13.25.15; Mon, 25 Nov 2019 13:25:39 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726029AbfKYVYG (ORCPT + 99 others); Mon, 25 Nov 2019 16:24:06 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:58252 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1725930AbfKYVYG (ORCPT ); Mon, 25 Nov 2019 16:24:06 -0500 Received: (qmail 5654 invoked by uid 2102); 25 Nov 2019 16:24:05 -0500 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 25 Nov 2019 16:24:05 -0500 Date: Mon, 25 Nov 2019 16:24:05 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: syzbot cc: andreyknvl@google.com, , , , , , Subject: Re: INFO: rcu detected stall in hub_event In-Reply-To: <00000000000003b7c305982885e3@google.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org #syz test: https://github.com/google/kasan.git 46178223 Index: usb-devel/drivers/hid/hid-core.c =================================================================== --- usb-devel.orig/drivers/hid/hid-core.c +++ usb-devel/drivers/hid/hid-core.c @@ -1057,6 +1057,8 @@ static void hid_apply_multiplier(struct while (multiplier_collection->parent_idx != -1 && multiplier_collection->type != HID_COLLECTION_LOGICAL) multiplier_collection = &hid->collection[multiplier_collection->parent_idx]; + if (multiplier_collection->type != HID_COLLECTION_LOGICAL) + multiplier_collection = NULL; effective_multiplier = hid_calculate_multiplier(hid, multiplier); @@ -1191,6 +1193,9 @@ int hid_open_report(struct hid_device *d } device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; + /* Needed for usages before the first collection */ + device->collection[0].parent_idx = -1; + ret = -EINVAL; while ((start = fetch_item(start, end, &item)) != NULL) {