From patchwork Wed Nov 18 13:37:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 11915099 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9EA10A6A for ; Wed, 18 Nov 2020 13:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79E99221FC for ; Wed, 18 Nov 2020 13:38:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726503AbgKRNiG (ORCPT ); Wed, 18 Nov 2020 08:38:06 -0500 Received: from mga18.intel.com ([134.134.136.126]:41354 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726216AbgKRNiG (ORCPT ); Wed, 18 Nov 2020 08:38:06 -0500 IronPort-SDR: j0bSVpWCzEPYzoMwzM4u5ofuGndkx7mMiBgkrw0/otJkg+e1RziXxHNoodNq1o9SWR2dOSi2kk krf5ykSAomrg== X-IronPort-AV: E=McAfee;i="6000,8403,9808"; a="158888395" X-IronPort-AV: E=Sophos;i="5.77,486,1596524400"; d="scan'208";a="158888395" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Nov 2020 05:37:50 -0800 IronPort-SDR: v7cTrv/KjhrAmyqlfQpl7rik/QWaJy2ivBss1qvxOAI2EnZK1fS5dnXRoamcDgq7RQsfka7XuC dYhsd0MsGxTw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,486,1596524400"; d="scan'208";a="341285756" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga002.jf.intel.com with ESMTP; 18 Nov 2020 05:37:46 -0800 Received: by black.fi.intel.com (Postfix, from userid 1001) id F3CB911E; Wed, 18 Nov 2020 15:37:45 +0200 (EET) From: Mika Westerberg To: linux-usb@vger.kernel.org Cc: Yehezkel Bernat , Michael Jamet , Paulian Bogdan Marinca , Andreas Noever , Lukas Wunner , Mika Westerberg Subject: [PATCH] thunderbolt: Fix use-after-free in remove_unplugged_switch() Date: Wed, 18 Nov 2020 16:37:45 +0300 Message-Id: <20201118133745.65628-1-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Paulian reported a crash that happens when a dock is unplugged during hibernation: [78436.228217] thunderbolt 0-1: device disconnected [78436.228365] BUG: kernel NULL pointer dereference, address: 00000000000001e0 ... [78436.228397] RIP: 0010:icm_free_unplugged_children+0x109/0x1a0 ... [78436.228432] Call Trace: [78436.228439] icm_rescan_work+0x24/0x30 [78436.228444] process_one_work+0x1a3/0x3a0 [78436.228449] worker_thread+0x30/0x370 [78436.228454] ? process_one_work+0x3a0/0x3a0 [78436.228457] kthread+0x13d/0x160 [78436.228461] ? kthread_park+0x90/0x90 [78436.228465] ret_from_fork+0x1f/0x30 This happens because remove_unplugged_switch() calls tb_switch_remove() that releases the memory pointed by sw so the following lines reference to a memory that might be released already. Fix this by saving pointer to the parent device before calling tb_switch_remove(). Reported-by: Paulian Bogdan Marinca Fixes: 4f7c2e0d8765 ("thunderbolt: Make sure device runtime resume completes before taking domain lock") Cc: stable@vger.kernel.org Signed-off-by: Mika Westerberg --- drivers/thunderbolt/icm.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c index b51fc3f62b1f..05323c442b56 100644 --- a/drivers/thunderbolt/icm.c +++ b/drivers/thunderbolt/icm.c @@ -1976,7 +1976,9 @@ static int complete_rpm(struct device *dev, void *data) static void remove_unplugged_switch(struct tb_switch *sw) { - pm_runtime_get_sync(sw->dev.parent); + struct device *parent = sw->dev.parent; + + pm_runtime_get_sync(parent); /* * Signal this and switches below for rpm_complete because @@ -1987,8 +1989,8 @@ static void remove_unplugged_switch(struct tb_switch *sw) bus_for_each_dev(&tb_bus_type, &sw->dev, NULL, complete_rpm); tb_switch_remove(sw); - pm_runtime_mark_last_busy(sw->dev.parent); - pm_runtime_put_autosuspend(sw->dev.parent); + pm_runtime_mark_last_busy(parent); + pm_runtime_put_autosuspend(parent); } static void icm_free_unplugged_children(struct tb_switch *sw)