From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Rose Subject: Re: [PATCH 3.0.y 3/3] rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo() Date: Fri, 4 Jan 2013 10:40:28 -0800 Message-ID: <20130104104028.000019ea@unknown> References: <1357259449.2685.60.camel@bwh-desktop.uk.solarflarecom.com> <1357259662.2685.63.camel@bwh-desktop.uk.solarflarecom.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Cc: Greg Kroah-Hartman , "David S. Miller" , Eric Dumazet , , , , To: Ben Hutchings Return-path: In-Reply-To: <1357259662.2685.63.camel@bwh-desktop.uk.solarflarecom.com> Sender: stable-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 4 Jan 2013 00:34:22 +0000 Ben Hutchings wrote: > From: Eric Dumazet > > commit a4b64fbe482c7766f7925f03067fc637716bfa3f upstream. > > nlmsg_parse() might return an error, so test its return value before > potential random memory accesses. > > Errors introduced in commit 115c9b81928 (rtnetlink: Fix problem with > buffer allocation) > > Signed-off-by: Eric Dumazet > Cc: Greg Rose > Signed-off-by: David S. Miller Acked-by: Greg Rose > --- > net/core/rtnetlink.c | 18 ++++++++++-------- > 1 files changed, 10 insertions(+), 8 deletions(-) > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c > index e41ce2a..49f281e 100644 > --- a/net/core/rtnetlink.c > +++ b/net/core/rtnetlink.c > @@ -1044,11 +1044,12 @@ static int rtnl_dump_ifinfo(struct sk_buff > *skb, struct netlink_callback *cb) > rcu_read_lock(); > > - nlmsg_parse(cb->nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX, > - ifla_policy); > + if (nlmsg_parse(cb->nlh, sizeof(struct rtgenmsg), tb, > IFLA_MAX, > + ifla_policy) >= 0) { > > - if (tb[IFLA_EXT_MASK]) > - ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]); > + if (tb[IFLA_EXT_MASK]) > + ext_filter_mask = > nla_get_u32(tb[IFLA_EXT_MASK]); > + } > > for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { > idx = 0; > @@ -1874,10 +1875,11 @@ static u16 rtnl_calcit(struct sk_buff *skb, > struct nlmsghdr *nlh) u32 ext_filter_mask = 0; > u16 min_ifinfo_dump_size = 0; > > - nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX, > ifla_policy); - > - if (tb[IFLA_EXT_MASK]) > - ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]); > + if (nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX, > + ifla_policy) >= 0) { > + if (tb[IFLA_EXT_MASK]) > + ext_filter_mask = > nla_get_u32(tb[IFLA_EXT_MASK]); > + } > > if (!ext_filter_mask) > return NLMSG_GOODSIZE; >