internal/netlink: set receive buffer size

This is done by both systemd sd-device and AOSP ueventd to improve robustness. Rosa OS will still handle ENOBUFS via coldboot but a big buffer should mitigate this as well.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/uevent/uevent.go

@@ -50,9 +50,9 @@ func (c *Conn) exitExcl() { c.excl.Store(false) }
 func (c *Conn) Close() error { return c.conn.Close() }
 
 // Dial returns the address of a newly connected [Conn].
-func Dial() (*Conn, error) {
+func Dial(rcvbuf int64) (*Conn, error) {
 	// kernel group is hard coded in lib/kobject_uevent.c, undocumented
-	c, err := netlink.Dial(syscall.NETLINK_KOBJECT_UEVENT, 1)
+	c, err := netlink.Dial(syscall.NETLINK_KOBJECT_UEVENT, 1, rcvbuf)
 	if err != nil {
 		return nil, err
 	}

internal/uevent/uevent_test.go

@@ -116,7 +116,7 @@ func adeB[V any, S interface {
 func TestDialConsume(t *testing.T) {
 	t.Parallel()
 
-	c, err := uevent.Dial()
+	c, err := uevent.Dial(0)
 	if err != nil {
 		t.Fatalf("Dial: error = %v", err)
 	}
@@ -127,7 +127,7 @@ func TestDialConsume(t *testing.T) {
 	})
 
 	// check kernel-assigned port id
-	c0, err0 := uevent.Dial()
+	c0, err0 := uevent.Dial(0)
 	if err0 != nil {
 		t.Fatalf("Dial: error = %v", err)
 	}