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 65C91C25B4E for ; Sun, 22 Jan 2023 15:08:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230215AbjAVPIU (ORCPT ); Sun, 22 Jan 2023 10:08:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230213AbjAVPIT (ORCPT ); Sun, 22 Jan 2023 10:08:19 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 938001C30E for ; Sun, 22 Jan 2023 07:08:18 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2F0C460C49 for ; Sun, 22 Jan 2023 15:08:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41C34C433D2; Sun, 22 Jan 2023 15:08:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1674400097; bh=wP4DLHxHqc0cM3X8kir7aCk0YWIDzAV+6pwOJZDoyhU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b9EgJiMGf/0BzkQPqTA3dT1LiXHBYVJqJK+ZT7TfdTUJ8DpkWIhVncBwpfg8/YUQY AezjpL7m7QhxWN/ZaWDiEEyU2c7bfcGuZZhBZSq/1KXjKp+3/EufqpFCnb60pXQNqk 6H6dd+ul+bTBDBe02bFRyglTqV1hA3+ShFkQ4y7c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mathias Nyman Subject: [PATCH 4.19 09/37] xhci: Fix null pointer dereference when host dies Date: Sun, 22 Jan 2023 16:04:06 +0100 Message-Id: <20230122150219.971826703@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230122150219.557984692@linuxfoundation.org> References: <20230122150219.557984692@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mathias Nyman commit a2bc47c43e70cf904b1af49f76d572326c08bca7 upstream. Make sure xhci_free_dev() and xhci_kill_endpoint_urbs() do not race and cause null pointer dereference when host suddenly dies. Usb core may call xhci_free_dev() which frees the xhci->devs[slot_id] virt device at the same time that xhci_kill_endpoint_urbs() tries to loop through all the device's endpoints, checking if there are any cancelled urbs left to give back. hold the xhci spinlock while freeing the virt device Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20230116142216.1141605-4-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3830,6 +3830,7 @@ static void xhci_free_dev(struct usb_hcd struct xhci_hcd *xhci = hcd_to_xhci(hcd); struct xhci_virt_device *virt_dev; struct xhci_slot_ctx *slot_ctx; + unsigned long flags; int i, ret; /* @@ -3859,7 +3860,11 @@ static void xhci_free_dev(struct usb_hcd xhci_debugfs_remove_slot(xhci, udev->slot_id); virt_dev->udev = NULL; xhci_disable_slot(xhci, udev->slot_id); + + spin_lock_irqsave(&xhci->lock, flags); xhci_free_virt_device(xhci, udev->slot_id); + spin_unlock_irqrestore(&xhci->lock, flags); + } int xhci_disable_slot(struct xhci_hcd *xhci, u32 slot_id)