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,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 17F9DC432C0 for ; Tue, 3 Dec 2019 22:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9A892053B for ; Tue, 3 Dec 2019 22:57:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413856; bh=h9hAePb4rgYiXNu8nffA2t81ggA4eShFI9X4lZFf2fs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=voZ/5uE0/VEfy19MJeMfn9bUjfruFR13pk9UMlQ/qQQoheB8EM+q7N8dauZ/N/ynv CVkp7I70OTJazFfySm0DBacz4gNw5US7a5gPDBjLwioRFDkDhK4yX0LP3YoRK7q5dx nODGvEUdjMnywKntxMMwr6rBGMywiRUwiQU4aQHU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730561AbfLCW5g (ORCPT ); Tue, 3 Dec 2019 17:57:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:53322 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730552AbfLCW5d (ORCPT ); Tue, 3 Dec 2019 17:57:33 -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 5070B2053B; Tue, 3 Dec 2019 22:57:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413852; bh=h9hAePb4rgYiXNu8nffA2t81ggA4eShFI9X4lZFf2fs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NaB0qSXGk0+qoW1h+XI9oIyQw5ZraglgVhA2MIQKrOxeImipIKVWZxtbi41DwqSQQ rLtGwMq6UPS5W2Qz8unFE5M5Nz8Lrr/S9/OWeg0Ks6/w/c74miy9tr0H709aZF7vua BIcv8av1KqKEJzPw6mEb45zqQbPNMZnlvWvBX/vk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+4d5170758f3762109542@syzkaller.appspotmail.com, David Miller , Oliver Hartkopp , Lukas Bulwahn , Jouni Hogander Subject: [PATCH 4.19 286/321] slip: Fix use-after-free Read in slip_open Date: Tue, 3 Dec 2019 23:35:52 +0100 Message-Id: <20191203223442.015989795@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191203223427.103571230@linuxfoundation.org> References: <20191203223427.103571230@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jouni Hogander [ Upstream commit e58c1912418980f57ba2060017583067f5f71e52 ] Slip_open doesn't clean-up device which registration failed from the slip_devs device list. On next open after failure this list is iterated and freed device is accessed. Fix this by calling sl_free_netdev in error path. Here is the trace from the Syzbot: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 sl_sync drivers/net/slip/slip.c:725 [inline] slip_open+0xecd/0x11b7 drivers/net/slip/slip.c:801 tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:469 tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:596 tiocsetd drivers/tty/tty_io.c:2334 [inline] tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2594 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 3b5a39979daf ("slip: Fix memory leak in slip_open error path") Reported-by: syzbot+4d5170758f3762109542@syzkaller.appspotmail.com Cc: David Miller Cc: Oliver Hartkopp Cc: Lukas Bulwahn Signed-off-by: Jouni Hogander Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/slip/slip.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/slip/slip.c +++ b/drivers/net/slip/slip.c @@ -855,6 +855,7 @@ err_free_chan: sl->tty = NULL; tty->disc_data = NULL; clear_bit(SLF_INUSE, &sl->flags); + sl_free_netdev(sl->dev); free_netdev(sl->dev); err_exit: