[PATCH 6.6 047/112] vsock/test: fix SEQPACKET message bounds test

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

6.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>

[ Upstream commit f0863888f6cfef33e3117dccfe94fa78edf76be4 ]

Tune message length calculation to make this test work on machines
where 'getpagesize()' returns >32KB. Now maximum message length is not
hardcoded (on machines above it was smaller than 'getpagesize()' return
value, thus we get negative value and test fails), but calculated at
runtime and always bigger than 'getpagesize()' result. Reproduced on
aarch64 with 64KB page size.

Fixes: 5c338112e48a ("test/vsock: rework message bounds test")
Signed-off-by: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>
Reported-by: Bogdan Marcynkov <bmarcynk@xxxxxxxxxx>
Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231121211642.163474-1-avkrasnov@xxxxxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 tools/testing/vsock/vsock_test.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index 90718c2fd4ea9..5dc7767039f6f 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -392,11 +392,12 @@ static void test_stream_msg_peek_server(const struct test_opts *opts)
 }
 
 #define SOCK_BUF_SIZE (2 * 1024 * 1024)
-#define MAX_MSG_SIZE (32 * 1024)
+#define MAX_MSG_PAGES 4
 
 static void test_seqpacket_msg_bounds_client(const struct test_opts *opts)
 {
 	unsigned long curr_hash;
+	size_t max_msg_size;
 	int page_size;
 	int msg_count;
 	int fd;
@@ -412,7 +413,8 @@ static void test_seqpacket_msg_bounds_client(const struct test_opts *opts)
 
 	curr_hash = 0;
 	page_size = getpagesize();
-	msg_count = SOCK_BUF_SIZE / MAX_MSG_SIZE;
+	max_msg_size = MAX_MSG_PAGES * page_size;
+	msg_count = SOCK_BUF_SIZE / max_msg_size;
 
 	for (int i = 0; i < msg_count; i++) {
 		ssize_t send_size;
@@ -423,7 +425,7 @@ static void test_seqpacket_msg_bounds_client(const struct test_opts *opts)
 		/* Use "small" buffers and "big" buffers. */
 		if (i & 1)
 			buf_size = page_size +
-					(rand() % (MAX_MSG_SIZE - page_size));
+					(rand() % (max_msg_size - page_size));
 		else
 			buf_size = 1 + (rand() % page_size);
 
@@ -479,7 +481,6 @@ static void test_seqpacket_msg_bounds_server(const struct test_opts *opts)
 	unsigned long remote_hash;
 	unsigned long curr_hash;
 	int fd;
-	char buf[MAX_MSG_SIZE];
 	struct msghdr msg = {0};
 	struct iovec iov = {0};
 
@@ -507,8 +508,13 @@ static void test_seqpacket_msg_bounds_server(const struct test_opts *opts)
 	control_writeln("SRVREADY");
 	/* Wait, until peer sends whole data. */
 	control_expectln("SENDDONE");
-	iov.iov_base = buf;
-	iov.iov_len = sizeof(buf);
+	iov.iov_len = MAX_MSG_PAGES * getpagesize();
+	iov.iov_base = malloc(iov.iov_len);
+	if (!iov.iov_base) {
+		perror("malloc");
+		exit(EXIT_FAILURE);
+	}
+
 	msg.msg_iov = &iov;
 	msg.msg_iovlen = 1;
 
@@ -533,6 +539,7 @@ static void test_seqpacket_msg_bounds_server(const struct test_opts *opts)
 		curr_hash += hash_djb2(msg.msg_iov[0].iov_base, recv_size);
 	}
 
+	free(iov.iov_base);
 	close(fd);
 	remote_hash = control_readulong();
 
-- 
2.42.0