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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 97E51C4332D for ; Thu, 19 Mar 2020 13:23:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E33A216FD for ; Thu, 19 Mar 2020 13:23:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584624208; bh=iYNgMw4vLnjc2E+zC4jx94Iy5zhCoIdL205SSdMGXNs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tu9C9+M4SCNN0dJcaap0nAvWTPH+q9guLkgiXznXWFDCCJSLaVCNUa8hwFEdaZVTN 4GwL2ImSvVXJ1GtdZZN6FgegCOV/C8+go8TZBKFB7P6DONPiHE9MbBvdyCwd8QD1DF A4l1T/Xg0G/Th7BsTiPQiSkPlS8Kg2Iw548irr30= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730342AbgCSNX0 (ORCPT ); Thu, 19 Mar 2020 09:23:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:49386 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730338AbgCSNXZ (ORCPT ); Thu, 19 Mar 2020 09:23:25 -0400 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 3BF0620724; Thu, 19 Mar 2020 13:23:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584624204; bh=iYNgMw4vLnjc2E+zC4jx94Iy5zhCoIdL205SSdMGXNs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zG2BeCbdYR+tO9l9bajUzEmpp1JwbK7vryW/hZVQOqAmKCsBkIDI9YTqv3q9cGxXE HtGDZJwQeX0F+8Or1iGUlnwjrQ4BOfmdWPR30UcNYOCR/LRDnb42E1+FQ6j0PrtJpl uJYeuOn63EHo1j0WK/OiZdMwQvjgD4Yhjg4mMEIs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Taehee Yoo , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 42/60] net: rmnet: fix NULL pointer dereference in rmnet_newlink() Date: Thu, 19 Mar 2020 14:04:20 +0100 Message-Id: <20200319123932.935535429@linuxfoundation.org> X-Mailer: git-send-email 2.25.2 In-Reply-To: <20200319123919.441695203@linuxfoundation.org> References: <20200319123919.441695203@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: Taehee Yoo [ Upstream commit 93b5cbfa9636d385126f211dca9efa7e3f683202 ] rmnet registers IFLA_LINK interface as a lower interface. But, IFLA_LINK could be NULL. In the current code, rmnet doesn't check IFLA_LINK. So, panic would occur. Test commands: modprobe rmnet ip link add rmnet0 type rmnet mux_id 1 Splat looks like: [ 36.826109][ T1115] general protection fault, probably for non-canonical address 0xdffffc0000000000I [ 36.838817][ T1115] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] [ 36.839908][ T1115] CPU: 1 PID: 1115 Comm: ip Not tainted 5.6.0-rc1+ #447 [ 36.840569][ T1115] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 36.841408][ T1115] RIP: 0010:rmnet_newlink+0x54/0x510 [rmnet] [ 36.841986][ T1115] Code: 83 ec 18 48 c1 e9 03 80 3c 01 00 0f 85 d4 03 00 00 48 8b 6a 28 48 b8 00 00 00 00 00 c [ 36.843923][ T1115] RSP: 0018:ffff8880b7e0f1c0 EFLAGS: 00010247 [ 36.844756][ T1115] RAX: dffffc0000000000 RBX: ffff8880d14cca00 RCX: 1ffff11016fc1e99 [ 36.845859][ T1115] RDX: 0000000000000000 RSI: ffff8880c3d04000 RDI: 0000000000000004 [ 36.846961][ T1115] RBP: 0000000000000000 R08: ffff8880b7e0f8b0 R09: ffff8880b6ac2d90 [ 36.848020][ T1115] R10: ffffffffc0589a40 R11: ffffed1016d585b7 R12: ffffffff88ceaf80 [ 36.848788][ T1115] R13: ffff8880c3d04000 R14: ffff8880b7e0f8b0 R15: ffff8880c3d04000 [ 36.849546][ T1115] FS: 00007f50ab3360c0(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000 [ 36.851784][ T1115] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.852422][ T1115] CR2: 000055871afe5ab0 CR3: 00000000ae246001 CR4: 00000000000606e0 [ 36.853181][ T1115] Call Trace: [ 36.853514][ T1115] __rtnl_newlink+0xbdb/0x1270 [ 36.853967][ T1115] ? lock_downgrade+0x6e0/0x6e0 [ 36.854420][ T1115] ? rtnl_link_unregister+0x220/0x220 [ 36.854936][ T1115] ? lock_acquire+0x164/0x3b0 [ 36.855376][ T1115] ? is_bpf_image_address+0xff/0x1d0 [ 36.855884][ T1115] ? rtnl_newlink+0x4c/0x90 [ 36.856304][ T1115] ? kernel_text_address+0x111/0x140 [ 36.856857][ T1115] ? __kernel_text_address+0xe/0x30 [ 36.857440][ T1115] ? unwind_get_return_address+0x5f/0xa0 [ 36.858063][ T1115] ? create_prof_cpu_mask+0x20/0x20 [ 36.858644][ T1115] ? arch_stack_walk+0x83/0xb0 [ 36.859171][ T1115] ? stack_trace_save+0x82/0xb0 [ 36.859710][ T1115] ? stack_trace_consume_entry+0x160/0x160 [ 36.860357][ T1115] ? deactivate_slab.isra.78+0x2c5/0x800 [ 36.860928][ T1115] ? kasan_unpoison_shadow+0x30/0x40 [ 36.861520][ T1115] ? kmem_cache_alloc_trace+0x135/0x350 [ 36.862125][ T1115] ? rtnl_newlink+0x4c/0x90 [ 36.864073][ T1115] rtnl_newlink+0x65/0x90 [ ... ] Fixes: ceed73a2cf4a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c index 06de59521fc4a..471e3b2a1403a 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c @@ -135,6 +135,11 @@ static int rmnet_newlink(struct net *src_net, struct net_device *dev, int err = 0; u16 mux_id; + if (!tb[IFLA_LINK]) { + NL_SET_ERR_MSG_MOD(extack, "link not specified"); + return -EINVAL; + } + real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK])); if (!real_dev || !dev) return -ENODEV; -- 2.20.1