inet: returns a bool from inet_sk_get_local_port_range()

Change inet_sk_get_local_port_range() to return a boolean,
telling the callers if the port range was provided by
IP_LOCAL_PORT_RANGE socket option.

Adds documentation while we are at it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20231214192939.1962891-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/ip.h b/include/net/ip.h
index b31be912489af8b01cc0393a27ffc80b086feaa0..de0c69c57e3cb7485e3d8473bc0b109e4280d2f6 100644 (file)
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -356,7 +356,7 @@ static inline void inet_get_local_port_range(const struct net *net, int *low, in
        *low = range & 0xffff;
        *high = range >> 16;
 }
-void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high);
+bool inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high);
 
 #ifdef CONFIG_SYSCTL
 static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 70be0f6fe879ea671bf6686b04edf32bf5e0d4b6..bd325b029dd12c9fad754ded266ae232ee7ec260 100644 (file)
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -117,16 +117,25 @@ bool inet_rcv_saddr_any(const struct sock *sk)
        return !sk->sk_rcv_saddr;
 }
 
-void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high)
+/**
+ *     inet_sk_get_local_port_range - fetch ephemeral ports range
+ *     @sk: socket
+ *     @low: pointer to low port
+ *     @high: pointer to high port
+ *
+ *     Fetch netns port range (/proc/sys/net/ipv4/ip_local_port_range)
+ *     Range can be overridden if socket got IP_LOCAL_PORT_RANGE option.
+ *     Returns true if IP_LOCAL_PORT_RANGE was set on this socket.
+ */
+bool inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high)
 {
-       const struct inet_sock *inet = inet_sk(sk);
-       const struct net *net = sock_net(sk);
        int lo, hi, sk_lo, sk_hi;
+       bool local_range = false;
        u32 sk_range;
 
-       inet_get_local_port_range(net, &lo, &hi);
+       inet_get_local_port_range(sock_net(sk), &lo, &hi);
 
-       sk_range = READ_ONCE(inet->local_port_range);
+       sk_range = READ_ONCE(inet_sk(sk)->local_port_range);
        if (unlikely(sk_range)) {
                sk_lo = sk_range & 0xffff;
                sk_hi = sk_range >> 16;
@@ -135,10 +144,12 @@ void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high)
                        lo = sk_lo;
                if (lo <= sk_hi && sk_hi <= hi)
                        hi = sk_hi;
+               local_range = true;
        }
 
        *low = lo;
        *high = hi;
+       return local_range;
 }
 EXPORT_SYMBOL(inet_sk_get_local_port_range);