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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B0E7C43215 for ; Wed, 27 Nov 2019 20:55:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0248C2084D for ; Wed, 27 Nov 2019 20:55:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574888103; bh=5sVxnb408V3TlrbZLrj+UKz2T8LnaptQoJmh3OJCdHg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ukQ7zFivm0+zOWqfg+Xnf9wlxyoVp8vNrSv+5yctgkO/N3VSm8v2czE8ocL6VOHhv 8/RVaO6xHTdqHtNElb7AWCvyJAZhHE4Lm+qV0JNfKOEC6OH78uLaZOr16GarqkLeBP m5ZBC15JhUuFZQCG8xf9gp53VqrvhT1FnRJ9GC7U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730263AbfK0UzC (ORCPT ); Wed, 27 Nov 2019 15:55:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:45372 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727955AbfK0UzB (ORCPT ); Wed, 27 Nov 2019 15:55:01 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C55C221556; Wed, 27 Nov 2019 20:54:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574888100; bh=5sVxnb408V3TlrbZLrj+UKz2T8LnaptQoJmh3OJCdHg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JPh5eyQBu9RZVSe7S+0vQvzO+kJ8sKQ7hjvVSCnX2dylroNZvPJbx09a6sIOBhhgs 0o7I1aC2HALKLqWFRYJbd2R9Hg8D7FdlKwsUiVB7XlCvrbAVBqsuttCo6k2n45Qcmq A8l/WUdkYcNb5aQpmc9IFPKYP8WUfbzKVmpeEJyU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Miller , Lukas Bulwahn , Jouni Hogander Subject: [PATCH 4.14 187/211] net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject Date: Wed, 27 Nov 2019 21:32:00 +0100 Message-Id: <20191127203111.387710023@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191127203049.431810767@linuxfoundation.org> References: <20191127203049.431810767@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jouni Hogander commit b8eb718348b8fb30b5a7d0a8fce26fb3f4ac741b upstream. kobject_init_and_add takes reference even when it fails. This has to be given up by the caller in error handling. Otherwise memory allocated by kobject_init_and_add is never freed. Originally found by Syzkaller: BUG: memory leak unreferenced object 0xffff8880679f8b08 (size 8): comm "netdev_register", pid 269, jiffies 4294693094 (age 12.132s) hex dump (first 8 bytes): 72 78 2d 30 00 36 20 d4 rx-0.6 . backtrace: [<000000008c93818e>] __kmalloc_track_caller+0x16e/0x290 [<000000001f2e4e49>] kvasprintf+0xb1/0x140 [<000000007f313394>] kvasprintf_const+0x56/0x160 [<00000000aeca11c8>] kobject_set_name_vargs+0x5b/0x140 [<0000000073a0367c>] kobject_init_and_add+0xd8/0x170 [<0000000088838e4b>] net_rx_queue_update_kobjects+0x152/0x560 [<000000006be5f104>] netdev_register_kobject+0x210/0x380 [<00000000e31dab9d>] register_netdevice+0xa1b/0xf00 [<00000000f68b2465>] __tun_chr_ioctl+0x20d5/0x3dd0 [<000000004c50599f>] tun_chr_ioctl+0x2f/0x40 [<00000000bbd4c317>] do_vfs_ioctl+0x1c7/0x1510 [<00000000d4c59e8f>] ksys_ioctl+0x99/0xb0 [<00000000946aea81>] __x64_sys_ioctl+0x78/0xb0 [<0000000038d946e5>] do_syscall_64+0x16f/0x580 [<00000000e0aa5d8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [<00000000285b3d1a>] 0xffffffffffffffff Cc: David Miller Cc: Lukas Bulwahn Signed-off-by: Jouni Hogander Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/net-sysfs.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -915,21 +915,23 @@ static int rx_queue_add_kobject(struct n error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL, "rx-%u", index); if (error) - return error; + goto err; dev_hold(queue->dev); if (dev->sysfs_rx_queue_group) { error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group); - if (error) { - kobject_put(kobj); - return error; - } + if (error) + goto err; } kobject_uevent(kobj, KOBJ_ADD); return error; + +err: + kobject_put(kobj); + return error; } #endif /* CONFIG_SYSFS */ @@ -1326,21 +1328,21 @@ static int netdev_queue_add_kobject(stru error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL, "tx-%u", index); if (error) - return error; + goto err; dev_hold(queue->dev); #ifdef CONFIG_BQL error = sysfs_create_group(kobj, &dql_group); - if (error) { - kobject_put(kobj); - return error; - } + if (error) + goto err; #endif kobject_uevent(kobj, KOBJ_ADD); - return 0; +err: + kobject_put(kobj); + return error; } #endif /* CONFIG_SYSFS */