diff --git a/tools/regression/sockets/sendfile/sendfile.c b/tools/regression/sockets/sendfile/sendfile.c
index c815824..0b27d95 100644
--- a/tools/regression/sockets/sendfile/sendfile.c
+++ b/tools/regression/sockets/sendfile/sendfile.c
@@ -27,6 +27,7 @@
  */
 
 #include <sys/types.h>
+#include <sys/mman.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
@@ -59,6 +60,7 @@
 #define	TEST_PORT	5678
 #define	TEST_MAGIC	0x4440f7bb
 #define	TEST_PAGES	4
+#define	TEST_EXTRA	100
 #define	TEST_SECONDS	30
 
 struct test_header {
@@ -345,7 +347,7 @@ run_parent(void)
 
 	const int pagesize = getpagesize();
 
-	struct sendfile_test tests[10] = {
+	struct sendfile_test tests[11] = {
  		{ .hdr_length = 0, .offset = 0, .length = 1 },
 		{ .hdr_length = 0, .offset = 0, .length = pagesize },
 		{ .hdr_length = 0, .offset = 1, .length = 1 },
@@ -355,12 +357,13 @@ run_parent(void)
 		{ .hdr_length = 0, .offset = 0, .length = 0 },
 		{ .hdr_length = 0, .offset = pagesize, .length = 0 },
 		{ .hdr_length = 0, .offset = 2*pagesize, .length = 0 },
-		{ .hdr_length = 0, .offset = TEST_PAGES*pagesize, .length = 0 }
+		{ .hdr_length = 0, .offset = TEST_PAGES*pagesize, .length = 0 },
+		{ .hdr_length = 0, .offset = 0, .length = TEST_PAGES*pagesize + TEST_EXTRA }
 	};
 
-	printf("1..10\n");
+	printf("1..11\n");
 
-	for (test_num = 1; test_num <= 10; test_num++) {
+	for (test_num = 1; test_num <= 11; test_num++) {
 
 		pid = fork();
 		if (pid == -1) {
@@ -412,22 +415,24 @@ main(void)
 {
 	char *page_buffer;
 	int pagesize;
+	int i;
 	ssize_t len;
+	caddr_t va;
 
 	*path = '\0';
 
 	pagesize = getpagesize();
-	page_buffer = malloc(TEST_PAGES * pagesize);
+	page_buffer = malloc(TEST_PAGES * pagesize + TEST_EXTRA);
 	if (page_buffer == NULL)
 		FAIL_ERR("malloc")
-	bzero(page_buffer, TEST_PAGES * pagesize);
+	bzero(page_buffer, TEST_PAGES * pagesize + TEST_EXTRA);
 
 	snprintf(path, PATH_MAX, "/tmp/sendfile.XXXXXXXXXXXX");
 	file_fd = mkstemp(path);
 	atexit(cleanup);
 
-	len = write(file_fd, page_buffer, TEST_PAGES * pagesize);
-	if (len < 0)
+	len = write(file_fd, page_buffer, TEST_PAGES * pagesize + TEST_EXTRA);
+	if (len != TEST_PAGES * pagesize + TEST_EXTRA)
 		FAIL_ERR("write")
 
 	len = lseek(file_fd, 0, SEEK_SET);
@@ -437,5 +442,19 @@ main(void)
 		FAIL("len != 0")
 
 	run_parent();
+#if 0
+	printf("read test\n");
+	len = read(file_fd, page_buffer, TEST_PAGES * pagesize + TEST_EXTRA);
+	if (len != TEST_PAGES * pagesize + TEST_EXTRA)
+		FAIL_ERR("read")
+#endif
+	printf("mmap test\n");
+	va = mmap(NULL, TEST_PAGES * pagesize + TEST_EXTRA, PROT_READ|PROT_WRITE, MAP_SHARED, file_fd, 0);
+	if (va == NULL)
+		FAIL_ERR("mmap");
+	for (i = 0; i < TEST_PAGES * pagesize + TEST_EXTRA; i++)
+		if (page_buffer[i] != va[i])
+			FAIL_ERR("mmap read");
+
 	return (0);
 }