From 33cf7c90fe2f97afb1cadaa0cfb782cb9d1b9ee2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 11 Mar 2015 18:53:14 -0700 Subject: net: add real socket cookies A long standing problem in netlink socket dumps is the use of kernel socket addresses as cookies. 1) It is a security concern. 2) Sockets can be reused quite quickly, so there is no guarantee a cookie is used once and identify a flow. 3) request sock, establish sock, and timewait socks for a given flow have different cookies. Part of our effort to bring better TCP statistics requires to switch to a different allocator. In this patch, I chose to use a per network namespace 64bit generator, and to use it only in the case a socket needs to be dumped to netlink. (This might be refined later if needed) Note that I tried to carry cookies from request sock, to establish sock, then timewait sockets. Signed-off-by: Eric Dumazet Cc: Eric Salo Signed-off-by: David S. Miller --- net/ipv4/inet_diag.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'net/ipv4/inet_diag.c') diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index ac3bfb458afd..29317ff4a007 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -221,12 +221,13 @@ static int inet_csk_diag_fill(struct sock *sk, user_ns, portid, seq, nlmsg_flags, unlh); } -static int inet_twsk_diag_fill(struct inet_timewait_sock *tw, +static int inet_twsk_diag_fill(struct sock *sk, struct sk_buff *skb, const struct inet_diag_req_v2 *req, u32 portid, u32 seq, u16 nlmsg_flags, const struct nlmsghdr *unlh) { + struct inet_timewait_sock *tw = inet_twsk(sk); struct inet_diag_msg *r; struct nlmsghdr *nlh; s32 tmo; @@ -247,7 +248,7 @@ static int inet_twsk_diag_fill(struct inet_timewait_sock *tw, r->idiag_retrans = 0; r->id.idiag_if = tw->tw_bound_dev_if; - sock_diag_save_cookie(tw, r->id.idiag_cookie); + sock_diag_save_cookie(sk, r->id.idiag_cookie); r->id.idiag_sport = tw->tw_sport; r->id.idiag_dport = tw->tw_dport; @@ -283,7 +284,7 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, const struct nlmsghdr *unlh) { if (sk->sk_state == TCP_TIME_WAIT) - return inet_twsk_diag_fill(inet_twsk(sk), skb, r, portid, seq, + return inet_twsk_diag_fill(sk, skb, r, portid, seq, nlmsg_flags, unlh); return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq, @@ -675,7 +676,7 @@ static int inet_twsk_diag_dump(struct sock *sk, if (!inet_diag_bc_sk(bc, sk)) return 0; - return inet_twsk_diag_fill(inet_twsk(sk), skb, r, + return inet_twsk_diag_fill(sk, skb, r, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh); } @@ -734,7 +735,10 @@ static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk, r->idiag_retrans = req->num_retrans; r->id.idiag_if = sk->sk_bound_dev_if; - sock_diag_save_cookie(req, r->id.idiag_cookie); + + BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) != + offsetof(struct sock, sk_cookie)); + sock_diag_save_cookie((struct sock *)ireq, r->id.idiag_cookie); tmo = req->expires - jiffies; if (tmo < 0) -- cgit