Message-ID: <d414e556-14ca-15ab-62b6-1e610b4828e9@sberdevices.ru>
Date:   Thu, 9 Mar 2023 23:29:26 +0300
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In-Reply-To: <1804d100-1652-d463-8627-da93cb61144e@sberdevices.ru>
To:     Stefan Hajnoczi <stefanha@redhat.com>,
        Stefano Garzarella <sgarzare@redhat.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Bobby Eshleman <bobby.eshleman@bytedance.com>
CC:     <kvm@vger.kernel.org>, <virtualization@lists.linux-foundation.org>,
        <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <kernel@sberdevices.ru>, <oxffffaa@gmail.com>,
        <avkrasnov@sberdevices.ru>
From:   Arseniy Krasnov <avkrasnov@sberdevices.ru>
Subject: [RFC PATCH v4 4/4] test/vsock: copy to user failure test
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Precedence: bulk

This adds SOCK_STREAM and SOCK_SEQPACKET tests for invalid buffer case.
It tries to read data to NULL buffer (data already presents in socket's
queue), then uses valid buffer. For SOCK_STREAM second read must return
data, because skbuff is not dropped, but for SOCK_SEQPACKET skbuff will
be dropped by kernel, and 'recv()' will return EAGAIN.

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 tools/testing/vsock/vsock_test.c | 118 +++++++++++++++++++++++++++++++
 1 file changed, 118 insertions(+)

diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
index 67e9f9df3a8c..3de10dbb50f5 100644
--- a/tools/testing/vsock/vsock_test.c
+++ b/tools/testing/vsock/vsock_test.c
@@ -860,6 +860,114 @@ static void test_stream_poll_rcvlowat_client(const struct test_opts *opts)
 	close(fd);
 }
 
+#define INV_BUF_TEST_DATA_LEN 512
+
+static void test_inv_buf_client(const struct test_opts *opts, bool stream)
+{
+	unsigned char data[INV_BUF_TEST_DATA_LEN] = {0};
+	ssize_t ret;
+	int fd;
+
+	if (stream)
+		fd = vsock_stream_connect(opts->peer_cid, 1234);
+	else
+		fd = vsock_seqpacket_connect(opts->peer_cid, 1234);
+
+	if (fd < 0) {
+		perror("connect");
+		exit(EXIT_FAILURE);
+	}
+
+	control_expectln("SENDDONE");
+
+	/* Use invalid buffer here. */
+	ret = recv(fd, NULL, sizeof(data), 0);
+	if (ret != -1) {
+		fprintf(stderr, "expected recv(2) failure, got %zi\n", ret);
+		exit(EXIT_FAILURE);
+	}
+
+	if (errno != ENOMEM) {
+		fprintf(stderr, "unexpected recv(2) errno %d\n", errno);
+		exit(EXIT_FAILURE);
+	}
+
+	ret = recv(fd, data, sizeof(data), MSG_DONTWAIT);
+
+	if (stream) {
+		/* For SOCK_STREAM we must continue reading. */
+		if (ret != sizeof(data)) {
+			fprintf(stderr, "expected recv(2) success, got %zi\n", ret);
+			exit(EXIT_FAILURE);
+		}
+		/* Don't check errno in case of success. */
+	} else {
+		/* For SOCK_SEQPACKET socket's queue must be empty. */
+		if (ret != -1) {
+			fprintf(stderr, "expected recv(2) failure, got %zi\n", ret);
+			exit(EXIT_FAILURE);
+		}
+
+		if (errno != EAGAIN) {
+			fprintf(stderr, "unexpected recv(2) errno %d\n", errno);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	control_writeln("DONE");
+
+	close(fd);
+}
+
+static void test_inv_buf_server(const struct test_opts *opts, bool stream)
+{
+	unsigned char data[INV_BUF_TEST_DATA_LEN] = {0};
+	ssize_t res;
+	int fd;
+
+	if (stream)
+		fd = vsock_stream_accept(VMADDR_CID_ANY, 1234, NULL);
+	else
+		fd = vsock_seqpacket_accept(VMADDR_CID_ANY, 1234, NULL);
+
+	if (fd < 0) {
+		perror("accept");
+		exit(EXIT_FAILURE);
+	}
+
+	res = send(fd, data, sizeof(data), 0);
+	if (res != sizeof(data)) {
+		fprintf(stderr, "unexpected send(2) result %zi\n", res);
+		exit(EXIT_FAILURE);
+	}
+
+	control_writeln("SENDDONE");
+
+	control_expectln("DONE");
+
+	close(fd);
+}
+
+static void test_stream_inv_buf_client(const struct test_opts *opts)
+{
+	test_inv_buf_client(opts, true);
+}
+
+static void test_stream_inv_buf_server(const struct test_opts *opts)
+{
+	test_inv_buf_server(opts, true);
+}
+
+static void test_seqpacket_inv_buf_client(const struct test_opts *opts)
+{
+	test_inv_buf_client(opts, false);
+}
+
+static void test_seqpacket_inv_buf_server(const struct test_opts *opts)
+{
+	test_inv_buf_server(opts, false);
+}
+
 static struct test_case test_cases[] = {
 	{
 		.name = "SOCK_STREAM connection reset",
@@ -920,6 +1028,16 @@ static struct test_case test_cases[] = {
 		.run_client = test_seqpacket_bigmsg_client,
 		.run_server = test_seqpacket_bigmsg_server,
 	},
+	{
+		.name = "SOCK_STREAM test invalid buffer",
+		.run_client = test_stream_inv_buf_client,
+		.run_server = test_stream_inv_buf_server,
+	},
+	{
+		.name = "SOCK_SEQPACKET test invalid buffer",
+		.run_client = test_seqpacket_inv_buf_client,
+		.run_server = test_seqpacket_inv_buf_server,
+	},
 	{},
 };
 
-- 
2.25.1