net: port < inet_prot_sock(net) --> inet_port_requires_bind_service(net, port)
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 <edumazet@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip.h b/include/net/ip.h
index cebf3e1..5a61bd9 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -351,9 +351,9 @@
return strcmp(name, "default") != 0 && strcmp(name, "all") != 0;
}
-static inline int inet_prot_sock(struct net *net)
+static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
{
- return net->ipv4.sysctl_ip_prot_sock;
+ return port < net->ipv4.sysctl_ip_prot_sock;
}
#else
@@ -362,9 +362,9 @@
return false;
}
-static inline int inet_prot_sock(struct net *net)
+static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
{
- return PROT_SOCK;
+ return port < PROT_SOCK;
}
#endif
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 53de8e0..2fe2954 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -495,7 +495,7 @@
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;
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index ef37e05..60e2ff9 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -292,7 +292,7 @@
return -EINVAL;
snum = ntohs(addr->sin6_port);
- 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))
return -EACCES;
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 3be7398..8d14a1a 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -423,7 +423,7 @@
if (!svc && protocol == IPPROTO_TCP &&
atomic_read(&ipvs->ftpsvc_counter) &&
- (vport == FTPDATA || ntohs(vport) >= inet_prot_sock(ipvs->net))) {
+ (vport == FTPDATA || !inet_port_requires_bind_service(ipvs->net, ntohs(vport)))) {
/*
* Check if ftp service entry exists, the packet
* might belong to FTP data connections.
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index e4c398d..0b48595 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -384,7 +384,7 @@
}
}
- 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))
return -EACCES;
@@ -1061,7 +1061,7 @@
if (sctp_autobind(sk))
return -EAGAIN;
} else {
- if (ep->base.bind_addr.port < inet_prot_sock(net) &&
+ if (inet_port_requires_bind_service(net, ep->base.bind_addr.port) &&
!ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
return -EACCES;
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9625b99..753b327 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4623,8 +4623,8 @@
inet_get_local_port_range(sock_net(sk), &low, &high);
- if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
- snum > high) {
+ if (inet_port_requires_bind_service(sock_net(sk), snum) ||
+ snum < low || snum > high) {
err = sel_netport_sid(sk->sk_protocol,
snum, &sid);
if (err)
