From 82f31ebf61bed3077c9935308e0a4b6c44842c5a Mon Sep 17 00:00:00 2001 From: Maciej Żenczykowski Date: Mon, 25 Nov 2019 15:37:04 -0800 Subject: net: port < inet_prot_sock(net) --> inet_port_requires_bind_service(net, port) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Note that the sysctl write accessor functions guarantee that: net->ipv4.sysctl_ip_prot_sock <= net->ipv4.ip_local_ports.range[0] invariant is maintained, and as such the max() in selinux hooks is actually spurious. ie. even though if (snum < max(inet_prot_sock(sock_net(sk)), low) || snum > high) { per logic is the same as if ((snum < inet_prot_sock(sock_net(sk)) && snum < low) || snum > high) { it is actually functionally equivalent to: if (snum < low || snum > high) { which is equivalent to: if (snum < inet_prot_sock(sock_net(sk)) || snum < low || snum > high) { even though the first clause is spurious. But we want to hold on to it in case we ever want to change what what inet_port_requires_bind_service() means (for example by changing it from a, by default, [0..1024) range to some sort of set). Test: builds, git 'grep inet_prot_sock' finds no other references Cc: Eric Dumazet Signed-off-by: Maciej Żenczykowski Signed-off-by: David S. Miller --- net/ipv4/af_inet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv4/af_inet.c') diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 53de8e00990e..2fe295432c24 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -495,7 +495,7 @@ int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len, snum = ntohs(addr->sin_port); err = -EACCES; - if (snum && snum < inet_prot_sock(net) && + if (snum && inet_port_requires_bind_service(net, snum) && !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) goto out; -- cgit v1.2.3-59-g8ed1b