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/core/sock.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 726e1f99aa8d..a9a9c2ff9260 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1538,6 +1538,7 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) newsk->sk_err = 0; newsk->sk_priority = 0; newsk->sk_incoming_cpu = raw_smp_processor_id(); + atomic64_set(&newsk->sk_cookie, 0); /* * Before updating sk_refcnt, we must commit prior changes to memory * (Documentation/RCU/rculist_nulls.txt for details) -- cgit v1.2.3