From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Haley Subject: Re: OOPS, ip -f inet6 route get fec0::1, linux-2.6.26, ip6_route_output, rt6_fill_node+0x175 Date: Fri, 08 Aug 2008 00:57:11 -0400 Message-ID: <489BD227.6000209@hp.com> References: <9F6ACAE02B6DD040A1E259977622CFDB033590C3@oslexcp1.eu.tandberg.int> <20080807203748.GA5196@martell.zuzino.mipt.ru> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------030209010905020208020707" Cc: John Gumb , linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: Alexey Dobriyan Return-path: Received: from g4t0017.houston.hp.com ([15.201.24.20]:36559 "EHLO g4t0017.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751365AbYHHE5n (ORCPT ); Fri, 8 Aug 2008 00:57:43 -0400 In-Reply-To: <20080807203748.GA5196@martell.zuzino.mipt.ru> Sender: netdev-owner@vger.kernel.org List-ID: This is a multi-part message in MIME format. --------------030209010905020208020707 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Alexey Dobriyan wrote: > On Thu, Aug 07, 2008 at 07:00:56PM +0200, John Gumb wrote: >> Scenario: no ipv6 default route set. > >> # ip -f inet6 route get fec0::1 >> >> BUG: unable to handle kernel NULL pointer dereference at 00000000 >> IP: [] rt6_fill_node+0x175/0x3b0 >> EIP is at rt6_fill_node+0x175/0x3b0 > > 0xffffffff80424dd3 is in rt6_fill_node (net/ipv6/route.c:2191). > 2186 } else > 2187 #endif > 2188 NLA_PUT_U32(skb, RTA_IIF, iif); > 2189 } else if (dst) { > 2190 struct in6_addr saddr_buf; > 2191 ====> if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev, > ^^^^^^^^^^^^^^^^^^^^^^^^ > NULL > > 2192 dst, 0, &saddr_buf) == 0) > 2193 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf); > 2194 } The commit that changed this can't be reverted easily, but the patch below works for me. Fix NULL de-reference in rt6_fill_node() when there's no IPv6 input device present in the dst entry. Signed-off-by: Brian Haley --------------030209010905020208020707 Content-Type: text/x-patch; name="idev.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="idev.patch" diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 5a3e87e..303a245 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2188,7 +2188,8 @@ static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt, NLA_PUT_U32(skb, RTA_IIF, iif); } else if (dst) { struct in6_addr saddr_buf; - if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev, + struct inet6_dev *idev = ip6_dst_idev(&rt->u.dst); + if (ipv6_dev_get_saddr(idev ? idev->dev : NULL, dst, 0, &saddr_buf) == 0) NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf); } --------------030209010905020208020707--