diff --git a/drivers/isimodem/voicecall.c b/drivers/isimodem/voicecall.c
index 9a63f100..3fb150f6 100644
--- a/drivers/isimodem/voicecall.c
+++ b/drivers/isimodem/voicecall.c
@@ -227,7 +227,7 @@ static void isi_call_any_address_sb_proc(struct isi_voicecall *ivc,
 
 	call->addr_type = type | 0x80;
 	call->presentation = pres;
-	strncpy(call->address, addr, sizeof(call->address));
+	strncpy(call->address, addr, sizeof(call->address) - 1);
 
 	g_free(addr);
 }