Commit f66ef469 authored by Michal Luczaj's avatar Michal Luczaj Committed by Jakub Kicinski
Browse files

vsock/test: Add test for accept_queue memory leak 



Attempt to enqueue a child after the queue was flushed, but before
SOCK_DONE flag has been set.

Test tries to produce a memory leak, kmemleak should be employed. Dealing
with a race condition, test by its very nature may lead to a false
negative.

Fixed by commit d7b0ff5a ("virtio/vsock: Fix accept_queue memory
leak").

Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: default avatarMichal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20241219-test-vsock-leaks-v4-5-a416e554d9d7@rbox.co


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f52e7f59

tools/testing/vsock/vsock_test.c

+52 −0
Original line number Diff line number Diff line
@@ -29,6 +29,10 @@ 
#include "control.h"

#include "util.h"



/* Basic messages for control_writeulong(), control_readulong() */

#define CONTROL_CONTINUE	1

#define CONTROL_DONE		0



static void test_stream_connection_reset(const struct test_opts *opts)

{

	union {
@@ -1474,6 +1478,49 @@ static void test_stream_cred_upd_on_set_rcvlowat(const struct test_opts *opts) 
	test_stream_credit_update_test(opts, false);

}



/* The goal of test leak_acceptq is to stress the race between connect() and

 * close(listener). Implementation of client/server loops boils down to:

 *

 * client                server

 * ------                ------

 * write(CONTINUE)

 *                       expect(CONTINUE)

 *                       listen()

 *                       write(LISTENING)

 * expect(LISTENING)

 * connect()             close()

 */

#define ACCEPTQ_LEAK_RACE_TIMEOUT 2 /* seconds */



static void test_stream_leak_acceptq_client(const struct test_opts *opts)

{

	time_t tout;

	int fd;



	tout = current_nsec() + ACCEPTQ_LEAK_RACE_TIMEOUT * NSEC_PER_SEC;

	do {

		control_writeulong(CONTROL_CONTINUE);



		fd = vsock_stream_connect(opts->peer_cid, opts->peer_port);

		if (fd >= 0)

			close(fd);

	} while (current_nsec() < tout);



	control_writeulong(CONTROL_DONE);

}



/* Test for a memory leak. User is expected to run kmemleak scan, see README. */

static void test_stream_leak_acceptq_server(const struct test_opts *opts)

{

	int fd;



	while (control_readulong() == CONTROL_CONTINUE) {

		fd = vsock_stream_listen(VMADDR_CID_ANY, opts->peer_port);

		control_writeln("LISTENING");

		close(fd);

	}

}



static struct test_case test_cases[] = {

	{

		.name = "SOCK_STREAM connection reset",
@@ -1604,6 +1651,11 @@ static struct test_case test_cases[] = { 
		.run_client = test_seqpacket_unsent_bytes_client,

		.run_server = test_seqpacket_unsent_bytes_server,

	},

	{

		.name = "SOCK_STREAM leak accept queue",

		.run_client = test_stream_leak_acceptq_client,

		.run_server = test_stream_leak_acceptq_server,

	},

	{},

};