From patchwork Tue Jan 14 13:09:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mohammed Gamal X-Patchwork-Id: 1222784 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=IFOhR3Fq; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47xrRv6bcjz9sPW for ; Wed, 15 Jan 2020 00:10:51 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726450AbgANNKu (ORCPT ); Tue, 14 Jan 2020 08:10:50 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:59905 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725904AbgANNKu (ORCPT ); Tue, 14 Jan 2020 08:10:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579007449; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=QYRkIRZn0ZoxpR/xXmi8xhkYGv+QH1Q2b0cVKYeNAcg=; b=IFOhR3Fq/DWXRczT2kKbMinWAkaaQpbQuNo6ogLBRaXHAlUUDJgxyyCyhXRZizZSNJGoAS FjLzlU+0rQQ6whWnrc3NWg851KQZqozg15UPwF4tF03STanvz+xSvFRZ4R+W2+4RVJSffQ UmgXzdiZXv4oHFkrOVgMnaqHprWhYHY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-131-X3bcbHaVMQW5sU9Eh-hs5A-1; Tue, 14 Jan 2020 08:10:45 -0500 X-MC-Unique: X3bcbHaVMQW5sU9Eh-hs5A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6BFB51902EC2; Tue, 14 Jan 2020 13:10:44 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-200-45.brq.redhat.com [10.40.200.45]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9DEC25E240; Tue, 14 Jan 2020 13:10:24 +0000 (UTC) From: Mohammed Gamal To: linux-hyperv@vger.kernel.org, sthemmin@microsoft.com, haiyangz@microsoft.com, netdev@vger.kernel.org Cc: kys@microsoft.com, sashal@kernel.org, vkuznets@redhat.com, cavery@redhat.com, linux-kernel@vger.kernel.org, Mohammed Gamal Subject: [PATCH v2] hv_netvsc: Fix memory leak when removing rndis device Date: Tue, 14 Jan 2020 15:09:50 +0200 Message-Id: <20200114130950.6962-1-mgamal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org kmemleak detects the following memory leak when hot removing a network device: unreferenced object 0xffff888083f63600 (size 256): comm "kworker/0:1", pid 12, jiffies 4294831717 (age 1113.676s) hex dump (first 32 bytes): 00 40 c7 33 80 88 ff ff 00 00 00 00 10 00 00 00 .@.3............ 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... backtrace: [<00000000d4a8f5be>] rndis_filter_device_add+0x117/0x11c0 [hv_netvsc] [<000000009c02d75b>] netvsc_probe+0x5e7/0xbf0 [hv_netvsc] [<00000000ddafce23>] vmbus_probe+0x74/0x170 [hv_vmbus] [<00000000046e64f1>] really_probe+0x22f/0xb50 [<000000005cc35eb7>] driver_probe_device+0x25e/0x370 [<0000000043c642b2>] bus_for_each_drv+0x11f/0x1b0 [<000000005e3d09f0>] __device_attach+0x1c6/0x2f0 [<00000000a72c362f>] bus_probe_device+0x1a6/0x260 [<0000000008478399>] device_add+0x10a3/0x18e0 [<00000000cf07b48c>] vmbus_device_register+0xe7/0x1e0 [hv_vmbus] [<00000000d46cf032>] vmbus_add_channel_work+0x8ab/0x1770 [hv_vmbus] [<000000002c94bb64>] process_one_work+0x919/0x17d0 [<0000000096de6781>] worker_thread+0x87/0xb40 [<00000000fbe7397e>] kthread+0x333/0x3f0 [<000000004f844269>] ret_from_fork+0x3a/0x50 rndis_filter_device_add() allocates an instance of struct rndis_device which never gets deallocated as rndis_filter_device_remove() sets net_device->extension which points to the rndis_device struct to NULL, leaving the rndis_device dangling. Since net_device->extension is eventually freed in free_netvsc_device(), we refrain from setting it to NULL inside rndis_filter_device_remove() Signed-off-by: Mohammed Gamal Reviewed-by: Haiyang Zhang --- drivers/net/hyperv/rndis_filter.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 857c4bea451c..e66d77dc28c8 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -1443,8 +1443,6 @@ void rndis_filter_device_remove(struct hv_device *dev, /* Halt and release the rndis device */ rndis_filter_halt_device(net_dev, rndis_dev); - net_dev->extension = NULL; - netvsc_device_remove(dev); }