From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: [PATCH] can: gs_usb: fixed disconnect bug by removing erroneous use of kfree() Date: Fri, 26 Feb 2016 08:42:58 +0100 Message-ID: <1456472578-16272-2-git-send-email-mkl@pengutronix.de> References: <1456472578-16272-1-git-send-email-mkl@pengutronix.de> Return-path: Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:56995 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753462AbcBZHnH (ORCPT ); Fri, 26 Feb 2016 02:43:07 -0500 In-Reply-To: <1456472578-16272-1-git-send-email-mkl@pengutronix.de> Sender: linux-can-owner@vger.kernel.org List-ID: To: netdev@vger.kernel.org Cc: davem@davemloft.net, linux-can@vger.kernel.org, kernel@pengutronix.de, Maximilain Schneider , linux-stable , Marc Kleine-Budde From: Maximilain Schneider gs_destroy_candev() erroneously calls kfree() on a struct gs_can *, which is allocated through alloc_candev() and should instead be freed using free_candev() alone. The inappropriate use of kfree() causes the kernel to hang when gs_destroy_candev() is called. Only the struct gs_usb * which is allocated through kzalloc() should be freed using kfree() when the device is disconnected. Signed-off-by: Maximilian Schneider Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/gs_usb.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c index 5eee62badf45..cbc99d5649af 100644 --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -826,9 +826,8 @@ static struct gs_can *gs_make_candev(unsigned int channel, struct usb_interface static void gs_destroy_candev(struct gs_can *dev) { unregister_candev(dev->netdev); - free_candev(dev->netdev); usb_kill_anchored_urbs(&dev->tx_submitted); - kfree(dev); + free_candev(dev->netdev); } static int gs_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) @@ -913,12 +912,15 @@ static int gs_usb_probe(struct usb_interface *intf, const struct usb_device_id * for (i = 0; i < icount; i++) { dev->canch[i] = gs_make_candev(i, intf); if (IS_ERR_OR_NULL(dev->canch[i])) { + /* save error code to return later */ + rc = PTR_ERR(dev->canch[i]); + /* on failure destroy previously created candevs */ icount = i; - for (i = 0; i < icount; i++) { + for (i = 0; i < icount; i++) gs_destroy_candev(dev->canch[i]); - dev->canch[i] = NULL; - } + + usb_kill_anchored_urbs(&dev->rx_submitted); kfree(dev); return rc; } @@ -939,16 +941,12 @@ static void gs_usb_disconnect(struct usb_interface *intf) return; } - for (i = 0; i < GS_MAX_INTF; i++) { - struct gs_can *can = dev->canch[i]; - - if (!can) - continue; - - gs_destroy_candev(can); - } + for (i = 0; i < GS_MAX_INTF; i++) + if (dev->canch[i]) + gs_destroy_candev(dev->canch[i]); usb_kill_anchored_urbs(&dev->rx_submitted); + kfree(dev); } static const struct usb_device_id gs_usb_table[] = { -- 2.7.0