From patchwork Fri Jan 4 00:34:22 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [3.0.y,3/3] rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo() Date: Thu, 03 Jan 2013 14:34:22 -0000 From: Ben Hutchings X-Patchwork-Id: 209343 Message-Id: <1357259662.2685.63.camel@bwh-desktop.uk.solarflarecom.com> To: Greg Kroah-Hartman Cc: "David S. Miller" , Eric Dumazet , Greg Rose , , , , 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;