xref: /freebsd/tests/sys/fs/fusefs/pre-init.cc (revision cc9c213086795fd821e6c17ee99a1db81a2141b2)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2025 ConnectWise
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 extern "C" {
29 #include <sys/param.h>
30 #include <sys/mount.h>
31 #include <sys/signal.h>
32 #include <sys/wait.h>
33 
34 #include <fcntl.h>
35 #include <pthread.h>
36 #include <semaphore.h>
37 #include <signal.h>
38 }
39 
40 #include "mockfs.hh"
41 #include "utils.hh"
42 
43 using namespace testing;
44 
45 /* Tests for behavior that happens before the server responds to FUSE_INIT */
46 class PreInit: public FuseTest {
SetUp()47 void SetUp() {
48 	m_no_auto_init = true;
49 	FuseTest::SetUp();
50 }
51 };
52 
unmount1(void * arg __unused)53 static void* unmount1(void* arg __unused) {
54 	ssize_t r;
55 
56 	r = unmount("mountpoint", 0);
57 	if (r >= 0)
58 		return 0;
59 	else
60 		return (void*)(intptr_t)errno;
61 }
62 
63 /*
64  * Attempting to unmount the file system before it fully initializes should
65  * work fine.  The unmount will complete after initialization does.
66  */
TEST_F(PreInit,unmount_before_init)67 TEST_F(PreInit, unmount_before_init)
68 {
69 	sem_t sem0;
70 	pthread_t th1;
71 
72 	ASSERT_EQ(0, sem_init(&sem0, 0, 0)) << strerror(errno);
73 
74 	EXPECT_CALL(*m_mock, process(
75 		ResultOf([](auto in) {
76 			return (in.header.opcode == FUSE_INIT);
77 		}, Eq(true)),
78 		_)
79 	).WillOnce(Invoke(ReturnImmediate([&](auto in, auto& out) {
80 		SET_OUT_HEADER_LEN(out, init);
81 		out.body.init.major = FUSE_KERNEL_VERSION;
82 		out.body.init.minor = FUSE_KERNEL_MINOR_VERSION;
83 		out.body.init.flags = in.body.init.flags & m_init_flags;
84 		out.body.init.max_write = m_maxwrite;
85 		out.body.init.max_readahead = m_maxreadahead;
86 		out.body.init.time_gran = m_time_gran;
87 		sem_wait(&sem0);
88 	})));
89 	expect_destroy(0);
90 
91 	ASSERT_EQ(0, pthread_create(&th1, NULL, unmount1, NULL));
92 	nap();	/* Wait for th1 to block in unmount() */
93 	sem_post(&sem0);
94 	/* The daemon will quit after receiving FUSE_DESTROY */
95 	m_mock->join_daemon();
96 }
97 
98 /*
99  * Don't panic in this very specific scenario:
100  *
101  * The server does not respond to FUSE_INIT in timely fashion.
102  * Some other process tries to do unmount.
103  * That other process gets killed by a signal.
104  * The server finally responds to FUSE_INIT.
105  *
106  * Regression test for bug 287438
107  * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=287438
108  */
TEST_F(PreInit,signal_during_unmount_before_init)109 TEST_F(PreInit, signal_during_unmount_before_init)
110 {
111 	sem_t sem0;
112 	pid_t child;
113 
114 	ASSERT_EQ(0, sem_init(&sem0, 0, 0)) << strerror(errno);
115 
116 	EXPECT_CALL(*m_mock, process(
117 		ResultOf([](auto in) {
118 			return (in.header.opcode == FUSE_INIT);
119 		}, Eq(true)),
120 		_)
121 	).WillOnce(Invoke(ReturnImmediate([&](auto in, auto& out) {
122 		SET_OUT_HEADER_LEN(out, init);
123 		out.body.init.major = FUSE_KERNEL_VERSION;
124 		/*
125 		 * Use protocol 7.19, like libfuse2 does.  The server must use
126 		 * protocol 7.27 or older to trigger the bug.
127 		 */
128 		out.body.init.minor = 19;
129 		out.body.init.flags = in.body.init.flags & m_init_flags;
130 		out.body.init.max_write = m_maxwrite;
131 		out.body.init.max_readahead = m_maxreadahead;
132 		out.body.init.time_gran = m_time_gran;
133 		sem_wait(&sem0);
134 	})));
135 
136 	if ((child = ::fork()) == 0) {
137 		/*
138 		 * In child.  This will block waiting for FUSE_INIT to complete
139 		 * or the receipt of an asynchronous signal.
140 		 */
141 		(void) unmount("mountpoint", 0);
142 		_exit(0);	/* Unreachable, unless parent dies after fork */
143 	} else if (child > 0) {
144 		/* In parent.  Wait for child process to start, then kill it */
145 		nap();
146 		kill(child, SIGINT);
147 		waitpid(child, NULL, WEXITED);
148 	} else {
149 		FAIL() << strerror(errno);
150 	}
151 	m_mock->m_quit = true;	/* Since we are by now unmounted. */
152 	sem_post(&sem0);
153 	m_mock->join_daemon();
154 }
155