[LTP] [PATCH v3] syscalls/recvmsg03.c: add new testcase

[Xiao Yang]

If the size of address for receiving data is set larger than
actaul size, recvmsg() will set msg_namelen incorrectly.

This bug has been fixed by the following kernel patch:
'commit 06b6a1cf6e77 ("rds: set correct msg_namelen")'

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 runtest/syscalls                              |   1 +
 testcases/kernel/syscalls/.gitignore          |   1 +
 testcases/kernel/syscalls/recvmsg/recvmsg03.c | 170 ++++++++++++++++++++++++++
 3 files changed, 172 insertions(+)
 create mode 100644 testcases/kernel/syscalls/recvmsg/recvmsg03.c

diff --git a/runtest/syscalls b/runtest/syscalls
index 2f2dde5..458cf2f 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -869,6 +869,7 @@ recvfrom01 recvfrom01
 
 recvmsg01 recvmsg01
 recvmsg02 recvmsg02
+recvmsg03 recvmsg03
 
 remap_file_pages01 remap_file_pages01
 remap_file_pages02 remap_file_pages02
diff --git a/testcases/kernel/syscalls/.gitignore b/testcases/kernel/syscalls/.gitignore
index 348c235..6377bd2 100644
--- a/testcases/kernel/syscalls/.gitignore
+++ b/testcases/kernel/syscalls/.gitignore
@@ -724,6 +724,7 @@
 /recvfrom/recvfrom01
 /recvmsg/recvmsg01
 /recvmsg/recvmsg02
+/recvmsg/recvmsg03
 /remap_file_pages/remap_file_pages01
 /remap_file_pages/remap_file_pages02
 /removexattr/removexattr01
diff --git a/testcases/kernel/syscalls/recvmsg/recvmsg03.c b/testcases/kernel/syscalls/recvmsg/recvmsg03.c
new file mode 100644
index 0000000..b23a7d1
--- /dev/null
+++ b/testcases/kernel/syscalls/recvmsg/recvmsg03.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright(c) 2016 Fujitsu Ltd.
+ * Author: Xiao Yang <yangx.jy@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU General Public License
+ * alone with this program.
+ */
+
+/*
+ * Test Name: recvmsg03
+ *
+ * This test needs that rds socket is supported by system.
+ * If the size of address for receiving data is set larger than
+ * actaul size, recvmsg() will set msg_namelen incorrectly.
+ *
+ * Description:
+ * This is a regression test and has been fixed by kernel commit:
+ * 06b6a1cf6e776426766298d055bb3991957d90a7 (rds: set correct msg_namelen)
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "tst_test.h"
+
+#ifndef AF_RDS
+# define AF_RDS 21
+#endif
+
+static void setup(void)
+{
+	int res;
+
+	res = socket(AF_RDS, SOCK_SEQPACKET, 0);
+	if (res == -1) {
+		if (errno == EAFNOSUPPORT)
+			tst_brk(TCONF, "rds was not supported");
+		else
+			tst_brk(TBROK | TERRNO, "socket() failed with rds");
+	}
+
+	SAFE_CLOSE(res);
+}
+
+static void client(void)
+{
+	TST_CHECKPOINT_WAIT(0);
+
+	int sock_fd1, count;
+	char send_buf[128] = "hello world";
+	struct sockaddr_in server_addr;
+	struct sockaddr_in to_addr;
+	struct msghdr msg;
+	struct iovec iov;
+
+	sock_fd1 = SAFE_SOCKET(AF_RDS, SOCK_SEQPACKET, 0);
+
+	memset(&server_addr, 0, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
+	server_addr.sin_port = htons(4001);
+
+	SAFE_BIND(sock_fd1, (struct sockaddr *) &server_addr, sizeof(server_addr));
+
+	memset(&to_addr, 0, sizeof(to_addr));
+
+	to_addr.sin_family = AF_INET;
+	to_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
+	to_addr.sin_port = htons(4000);
+	msg.msg_name = &to_addr;
+	msg.msg_namelen = sizeof(to_addr);
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_iov->iov_base = send_buf;
+	msg.msg_iov->iov_len = strlen(send_buf) + 1;
+	msg.msg_control = 0;
+	msg.msg_controllen = 0;
+	msg.msg_flags = 0;
+
+	/* make sure that recvmsg() can succeed to get data.
+	 * we may not send data successfully when loading rds
+	 * module for the first time.
+	 */
+	for (count = 1; count < 5000; count++) {
+		if (sendmsg(sock_fd1, &msg, 0) == -1) {
+			tst_brk(TBROK | TERRNO,
+				"sendmsg() failed to send data to server");
+		}
+	}
+
+	SAFE_CLOSE(sock_fd1);
+}
+
+static void server(void)
+{
+	int sock_fd2;
+	static char recv_buf[128];
+	struct sockaddr_in server_addr;
+	struct sockaddr_in from_addr;
+	struct msghdr msg;
+	struct iovec iov;
+
+	sock_fd2 = SAFE_SOCKET(AF_RDS, SOCK_SEQPACKET, 0);
+
+	memset(&server_addr, 0, sizeof(server_addr));
+	server_addr.sin_family = AF_INET;
+	server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
+	server_addr.sin_port = htons(4000);
+
+	SAFE_BIND(sock_fd2, (struct sockaddr *) &server_addr, sizeof(server_addr));
+
+	msg.msg_name = &from_addr;
+	msg.msg_namelen = sizeof(from_addr) + 16;
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_iov->iov_base = recv_buf;
+	msg.msg_iov->iov_len = 128;
+	msg.msg_control = 0;
+	msg.msg_controllen = 0;
+	msg.msg_flags = 0;
+
+	TST_CHECKPOINT_WAKE(0);
+
+	TEST(recvmsg(sock_fd2, &msg, 0));
+	if (TEST_RETURN == -1) {
+		tst_brk(TBROK | TTERRNO,
+		"recvmsg() failed to recvice data from client");
+	}
+
+	if (msg.msg_namelen != sizeof(from_addr)) {
+		tst_res(TFAIL, "msg_namelen was set to %u incorrectly, "
+			"expected %lu", msg.msg_namelen, sizeof(from_addr));
+	} else {
+		tst_res(TPASS, "msg_namelen was set to %u correctly",
+			msg.msg_namelen);
+	}
+
+	SAFE_CLOSE(sock_fd2);
+}
+
+static void verify_recvmsg(void)
+{
+	pid_t pid;
+
+	pid = SAFE_FORK();
+	if (pid == 0) {
+		client();
+	} else {
+		server();
+		tst_reap_children();
+	}
+}
+
+static struct tst_test test = {
+	.tid = "recvmsg03",
+	.forks_child = 1,
+	.needs_checkpoints = 1,
+	.setup = setup,
+	.test_all = verify_recvmsg
+};
-- 
1.8.3.1