From patchwork Fri Nov 15 12:24:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jouni =?utf-8?Q?H=C3=B6gander?= X-Patchwork-Id: 1195596 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=none (p=none dis=none) header.from=unikie.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=unikie-com.20150623.gappssmtp.com header.i=@unikie-com.20150623.gappssmtp.com header.b="psy+B1bE"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47DyG85SLpz9sPK for ; Fri, 15 Nov 2019 23:24:32 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727573AbfKOMYa (ORCPT ); Fri, 15 Nov 2019 07:24:30 -0500 Received: from mail-lj1-f196.google.com ([209.85.208.196]:42834 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727200AbfKOMY3 (ORCPT ); Fri, 15 Nov 2019 07:24:29 -0500 Received: by mail-lj1-f196.google.com with SMTP id n5so10483124ljc.9 for ; Fri, 15 Nov 2019 04:24:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=unikie-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=bzv6XndTwiYdKwJoxLwMZ+hMreX7E/3CphCS/5v6cp0=; b=psy+B1bEoEB+Jt3zNXyhlhkv7hz9QrzCGzkyGg/R2J6R0+saZR+xgxU2z4+qvbFHY6 sIe+pEO/FyauUw0U+T0f6/Bjp22T+DEjJHBoBPsgkRZPdEmTFj1mbzV/OdRKd1M0mPGz lSQDvTaB3IAuFCsesfsUcfGD6FnhlWDl9wPzW2ItK55OlJocscxj9zO8dyFrH6fQTiRh LbXjJpLfyhfAjEb7wLCM2TkUcpgTVx7jsoqLHYgpSbjihVDWEIO1ajO42wVaGOyp7HFH H6q+xZV5rXpIYYb+vdcOhKeqkb0sHiKyAUhyOXkrQMvo3BZQlbk+bEEPYPpUNUuZKOrx /0cA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=bzv6XndTwiYdKwJoxLwMZ+hMreX7E/3CphCS/5v6cp0=; b=KXbfTLQdm/Ll82/Hw3uBhec1B9degXQvuj2BXvCv9B2OcFbfLeSxWJ4JAnJOMLT0Bc HBPSNiNA8mDuCaQeyGRiKB4yw81IaL3XmU7ixiCoJu7ROZ3DAMFsTkFDzm6nUwstkB16 vnlHZwR+PFb8Jmszc5B+Y2cctwDphQcIR1wYrjB7PmBP6LSl3eC8dgXPr4U+7N+Dq7cL ChvL8trPuGtvWP9bE1IT/V+xs8j7PJKrCZUc1+N6k+Zh39AoIQbSXYnm+uSgegah5iqi vGtwYvWidLm1hOyZ7ijlSIXOSdjpQEBTMiQPw+J785Fg8GNVH4KxR21PMPmOOiDKPwnr csQA== X-Gm-Message-State: APjAAAU3OoJfg3bCz/29MOS3eHwE7BVKAWI/ZP0OOQOJOMjgTZUcQ9i5 Caj+ms9hIlWJSLMeDD+wDBor3Ru6kCY= X-Google-Smtp-Source: APXvYqwLV6rTZf0f4qgfoh+vBw9ypl2I4IyXzmLHtdAr+C1kndiv6MGnameGYe0+L3RCs+NfiKvFnQ== X-Received: by 2002:a2e:b0d9:: with SMTP id g25mr10471242ljl.176.1573820667102; Fri, 15 Nov 2019 04:24:27 -0800 (PST) Received: from localhost.localdomain ([109.204.235.119]) by smtp.gmail.com with ESMTPSA id b28sm4525060ljp.9.2019.11.15.04.24.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Nov 2019 04:24:26 -0800 (PST) From: jouni.hogander@unikie.com To: netdev@vger.kernel.org Cc: Jouni Hogander , David Miller , Greg Kroah-Hartman , Lukas Bulwahn Subject: [PATCH] net-sysfs: Fix reference count leak Date: Fri, 15 Nov 2019 14:24:12 +0200 Message-Id: <20191115122412.2595-1-jouni.hogander@unikie.com> X-Mailer: git-send-email 2.17.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jouni Hogander Netdev_register_kobject is calling device_initialize. In case of error reference taken by device_initialize is not given up. This is the rootcause for couple of memory leaks reported by Syzkaller: BUG: memory leak unreferenced object 0xffff8880675ca008 (size 256): comm "netdev_register", pid 281, jiffies 4294696663 (age 6.808s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000058ca4711>] kmem_cache_alloc_trace+0x167/0x280 [<000000002340019b>] device_add+0x882/0x1750 [<000000001d588c3a>] netdev_register_kobject+0x128/0x380 [<0000000011ef5535>] register_netdevice+0xa1b/0xf00 [<000000007fcf1c99>] __tun_chr_ioctl+0x20d5/0x3dd0 [<000000006a5b7b2b>] tun_chr_ioctl+0x2f/0x40 [<00000000f30f834a>] do_vfs_ioctl+0x1c7/0x1510 [<00000000fba062ea>] ksys_ioctl+0x99/0xb0 [<00000000b1c1b8d2>] __x64_sys_ioctl+0x78/0xb0 [<00000000984cabb9>] do_syscall_64+0x16f/0x580 [<000000000bde033d>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [<00000000e6ca2d9f>] 0xffffffffffffffff BUG: memory leak unreferenced object 0xffff8880668ba588 (size 8): comm "kobject_set_nam", pid 286, jiffies 4294725297 (age 9.871s) hex dump (first 8 bytes): 6e 72 30 00 cc be df 2b nr0....+ backtrace: [<00000000a322332a>] __kmalloc_track_caller+0x16e/0x290 [<00000000236fd26b>] kstrdup+0x3e/0x70 [<00000000dd4a2815>] kstrdup_const+0x3e/0x50 [<0000000049a377fc>] kvasprintf_const+0x10e/0x160 [<00000000627fc711>] kobject_set_name_vargs+0x5b/0x140 [<0000000019eeab06>] dev_set_name+0xc0/0xf0 [<0000000069cb12bc>] netdev_register_kobject+0xc8/0x320 [<00000000f2e83732>] register_netdevice+0xa1b/0xf00 [<000000009e1f57cc>] __tun_chr_ioctl+0x20d5/0x3dd0 [<000000009c560784>] tun_chr_ioctl+0x2f/0x40 [<000000000d759e02>] do_vfs_ioctl+0x1c7/0x1510 [<00000000351d7c31>] ksys_ioctl+0x99/0xb0 [<000000008390040a>] __x64_sys_ioctl+0x78/0xb0 [<0000000052d196b7>] do_syscall_64+0x16f/0x580 [<0000000019af9236>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [<00000000bc384531>] 0xffffffffffffffff Reported-by: syzbot+ad8ca40ecd77896d51e2@syzkaller.appspotmail.com Cc: David Miller Cc: Greg Kroah-Hartman Cc: Lukas Bulwahn Signed-off-by: Jouni Hogander --- net/core/net-sysfs.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 865ba6ca16eb..72ecad583953 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1626,6 +1626,12 @@ static void netdev_release(struct device *d) { struct net_device *dev = to_net_dev(d); + /* Triggered by an error clean-up (put_device) during + * initialization. + */ + if (dev->reg_state == NETREG_UNINITIALIZED) + return; + BUG_ON(dev->reg_state != NETREG_RELEASED); /* no need to wait for rcu grace period: @@ -1745,16 +1751,21 @@ int netdev_register_kobject(struct net_device *ndev) error = device_add(dev); if (error) - return error; + goto err_device_add; error = register_queue_kobjects(ndev); - if (error) { - device_del(dev); - return error; - } + if (error) + goto err_register_queue_kobjects; pm_runtime_set_memalloc_noio(dev, true); + return error; + +err_register_queue_kobjects: + device_del(dev); +err_device_add: + put_device(dev); + return error; }