[PATCH mptcp-net v3 2/8] mptcp: pm: userspace: lookup: match port in priority

In the local address list, there can be entries with the port set to 0
-- corresponding to the source port used by the initial subflow -- and
others with a specific port.

When performing a lookup, it is important to compare the ports to pick
the right entry: when a specific port is given, then try to match it
first. If no match is found, try to find entries with the port set to 0.

Fixes: 24430f8bf516 ("mptcp: add address into userspace pm list")
Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>
---
v3: new (Sashiko)
---
 net/mptcp/pm_userspace.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 663cbeb79548..3f1471ec3fc7 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -33,10 +33,22 @@ mptcp_userspace_pm_lookup_addr(struct mptcp_sock *msk,
 {
 	struct mptcp_pm_addr_entry *entry;
 
+	/* Compare ports when set in addr */
 	mptcp_for_each_userspace_pm_addr(msk, entry) {
-		if (mptcp_addresses_equal(&entry->addr, addr, false))
+		if (mptcp_addresses_equal(&entry->addr, addr, addr->port != 0))
 			return entry;
 	}
+
+	if (addr->port == 0)
+		return NULL;
+
+	/* Check only wildcard ports if no exact match with the port */
+	mptcp_for_each_userspace_pm_addr(msk, entry) {
+		if (entry->addr.port == 0 &&
+		    mptcp_addresses_equal(&entry->addr, addr, false))
+			return entry;
+	}
+
 	return NULL;
 }
 

-- 
2.53.0