| From d87e50221186c9d7e21b99fc770248aa3b61c26c Mon Sep 17 00:00:00 2001 |
| From: Pablo Neira Ayuso <pablo@netfilter.org> |
| Date: Wed, 26 Feb 2020 19:47:34 +0100 |
| Subject: [PATCH] netlink: Use netlink header as base to calculate bad |
| attribute offset |
| |
| commit 84b3268027641401bb8ad4427a90a3cce2eb86f5 upstream. |
| |
| Userspace might send a batch that is composed of several netlink |
| messages. The netlink_ack() function must use the pointer to the netlink |
| header as base to calculate the bad attribute offset. |
| |
| Fixes: 2d4bc93368f5 ("netlink: extended ACK reporting") |
| Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c |
| index bd056ec269f1..b7db1f99fc70 100644 |
| --- a/net/netlink/af_netlink.c |
| +++ b/net/netlink/af_netlink.c |
| @@ -2439,7 +2439,7 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, |
| in_skb->len)) |
| WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, |
| (u8 *)extack->bad_attr - |
| - in_skb->data)); |
| + (u8 *)nlh)); |
| } else { |
| if (extack->cookie_len) |
| WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, |
| -- |
| 2.7.4 |
| |
