1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <gtest/gtest.h>
18 
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <string.h>
22 #include <sys/utsname.h>
23 #include <sys/vfs.h>
24 
25 #include <android-base/file.h>
26 #include <android-base/silent_death_test.h>
27 #include <android-base/stringprintf.h>
28 
29 // Glibc v2.19 doesn't include these in fcntl.h so host builds will fail without.
30 #if !defined(FALLOC_FL_PUNCH_HOLE) || !defined(FALLOC_FL_KEEP_SIZE)
31 #include <linux/falloc.h>
32 #endif
33 #if !defined(EXT4_SUPER_MAGIC)
34 #include <linux/magic.h>
35 #endif
36 
37 #include "utils.h"
38 
39 using fcntl_DeathTest = SilentDeathTest;
40 
TEST(fcntl,fcntl_smoke)41 TEST(fcntl, fcntl_smoke) {
42   int fd = open("/proc/version", O_RDONLY);
43   ASSERT_TRUE(fd != -1);
44 
45   int flags = fcntl(fd, F_GETFD);
46   ASSERT_TRUE(flags != -1);
47   ASSERT_EQ(0, flags & FD_CLOEXEC);
48 
49   int rc = fcntl(fd, F_SETFD, FD_CLOEXEC);
50   ASSERT_EQ(0, rc);
51 
52   flags = fcntl(fd, F_GETFD);
53   ASSERT_TRUE(flags != -1);
54   ASSERT_EQ(FD_CLOEXEC, flags & FD_CLOEXEC);
55 
56   close(fd);
57 }
58 
TEST(fcntl,open_open64)59 TEST(fcntl, open_open64) {
60   int fd;
61 
62   fd = open("/proc/version", O_RDONLY);
63   ASSERT_TRUE(fd != -1);
64   close(fd);
65 
66   fd = open64("/proc/version", O_RDONLY);
67   ASSERT_TRUE(fd != -1);
68   close(fd);
69 }
70 
TEST(fcntl,openat_openat64)71 TEST(fcntl, openat_openat64) {
72   int fd;
73 
74   fd = openat(AT_FDCWD, "/proc/version", O_RDONLY);
75   ASSERT_TRUE(fd != -1);
76   close(fd);
77 
78   fd = openat64(AT_FDCWD, "/proc/version", O_RDONLY);
79   ASSERT_TRUE(fd != -1);
80   close(fd);
81 }
82 
TEST(fcntl,creat_creat64)83 TEST(fcntl, creat_creat64) {
84   ASSERT_EQ(-1, creat("", 0666));
85   ASSERT_ERRNO(ENOENT);
86   ASSERT_EQ(-1, creat64("", 0666));
87   ASSERT_ERRNO(ENOENT);
88 }
89 
TEST(fcntl,posix_fadvise)90 TEST(fcntl, posix_fadvise) {
91   TemporaryFile tf;
92   errno = 0;
93 
94   EXPECT_EQ(EBADF, posix_fadvise(-1, 0, 0, POSIX_FADV_NORMAL));
95   EXPECT_ERRNO(0);
96 
97   EXPECT_EQ(EBADF, posix_fadvise64(-1, 0, 0, POSIX_FADV_NORMAL));
98   EXPECT_ERRNO(0);
99 
100   EXPECT_EQ(EINVAL, posix_fadvise(tf.fd, 0, 0, -1));
101   EXPECT_ERRNO(0);
102 
103   EXPECT_EQ(EINVAL, posix_fadvise64(tf.fd, 0, 0, -1));
104   EXPECT_ERRNO(0);
105 
106   EXPECT_EQ(0, posix_fadvise(tf.fd, 0, 0, POSIX_FADV_NORMAL));
107   EXPECT_EQ(0, posix_fadvise64(tf.fd, 0, 0, POSIX_FADV_NORMAL));
108 }
109 
TEST(fcntl,fallocate_EINVAL)110 TEST(fcntl, fallocate_EINVAL) {
111   TemporaryFile tf;
112 
113   // fallocate/fallocate64 set errno.
114   // posix_fallocate/posix_fallocate64 return an errno value.
115 
116   errno = 0;
117   ASSERT_EQ(-1, fallocate(tf.fd, 0, 0, -1));
118   ASSERT_ERRNO(EINVAL);
119 
120   errno = 0;
121   ASSERT_EQ(-1, fallocate64(tf.fd, 0, 0, -1));
122   ASSERT_ERRNO(EINVAL);
123 
124   errno = 0;
125   ASSERT_EQ(EINVAL, posix_fallocate(tf.fd, 0, -1));
126   ASSERT_ERRNO(0);
127 
128   errno = 0;
129   ASSERT_EQ(EINVAL, posix_fallocate64(tf.fd, 0, -1));
130   ASSERT_ERRNO(0);
131 }
132 
TEST(fcntl,fallocate)133 TEST(fcntl, fallocate) {
134   TemporaryFile tf;
135   struct stat sb;
136   ASSERT_EQ(0, fstat(tf.fd, &sb));
137   ASSERT_EQ(0, sb.st_size);
138 
139 #if defined(__BIONIC__)
140   ASSERT_EQ(0, fallocate(tf.fd, 0, 0, 1));
141   ASSERT_EQ(0, fstat(tf.fd, &sb));
142   ASSERT_EQ(1, sb.st_size);
143 
144   ASSERT_EQ(0, fallocate64(tf.fd, 0, 0, 2));
145   ASSERT_EQ(0, fstat(tf.fd, &sb));
146   ASSERT_EQ(2, sb.st_size);
147 #endif
148 
149   ASSERT_EQ(0, posix_fallocate(tf.fd, 0, 3));
150   ASSERT_EQ(0, fstat(tf.fd, &sb));
151   ASSERT_EQ(3, sb.st_size);
152 
153   ASSERT_EQ(0, posix_fallocate64(tf.fd, 0, 4));
154   ASSERT_EQ(0, fstat(tf.fd, &sb));
155   ASSERT_EQ(4, sb.st_size);
156 }
157 
TEST(fcntl,f_getlk)158 TEST(fcntl, f_getlk) {
159   int fd = open("/proc/version", O_RDONLY);
160   ASSERT_TRUE(fd != -1);
161 
162   struct flock check_lock;
163   check_lock.l_type = F_WRLCK;
164   check_lock.l_start = 0;
165   check_lock.l_whence = SEEK_SET;
166   check_lock.l_len = 0;
167 
168   ASSERT_EQ(0, fcntl(fd, F_GETLK, &check_lock));
169   close(fd);
170 }
171 
TEST(fcntl,f_getlk64)172 TEST(fcntl, f_getlk64) {
173   int fd = open64("/proc/version", O_RDONLY);
174   ASSERT_TRUE(fd != -1);
175 
176   struct flock64 check_lock;
177   check_lock.l_type = F_WRLCK;
178   check_lock.l_start = 0;
179   check_lock.l_whence = SEEK_SET;
180   check_lock.l_len = 0;
181 
182   ASSERT_EQ(0, fcntl(fd, F_GETLK64, &check_lock));
183   close(fd);
184 }
185 
TEST(fcntl,splice)186 TEST(fcntl, splice) {
187   int pipe_fds[2];
188   ASSERT_EQ(0, pipe(pipe_fds));
189 
190   int in = open("/proc/cpuinfo", O_RDONLY);
191   ASSERT_NE(in, -1);
192 
193   TemporaryFile tf;
194 
195   ssize_t bytes_read = splice(in, nullptr, pipe_fds[1], nullptr, 8*1024, SPLICE_F_MORE | SPLICE_F_MOVE);
196   ASSERT_NE(bytes_read, -1);
197 
198   ssize_t bytes_written = splice(pipe_fds[0], nullptr, tf.fd, nullptr, bytes_read, SPLICE_F_MORE | SPLICE_F_MOVE);
199   ASSERT_EQ(bytes_read, bytes_written);
200 
201   close(pipe_fds[0]);
202   close(pipe_fds[1]);
203   close(in);
204 }
205 
TEST(fcntl,vmsplice)206 TEST(fcntl, vmsplice) {
207   int pipe_fds[2];
208   ASSERT_EQ(0, pipe(pipe_fds));
209 
210   iovec v[2];
211   v[0].iov_base = const_cast<char*>("hello ");
212   v[0].iov_len = 6;
213   v[1].iov_base = const_cast<char*>("world\n");
214   v[1].iov_len = 6;
215   ssize_t bytes_written = vmsplice(pipe_fds[1], v, sizeof(v)/sizeof(iovec), 0);
216   ASSERT_EQ(v[0].iov_len + v[1].iov_len, static_cast<size_t>(bytes_written));
217   close(pipe_fds[1]);
218 
219   char buf[BUFSIZ];
220   FILE* fp = fdopen(pipe_fds[0], "r");
221   ASSERT_TRUE(fp != nullptr);
222   ASSERT_TRUE(fgets(buf, sizeof(buf), fp) != nullptr);
223   fclose(fp);
224   ASSERT_STREQ("hello world\n", buf);
225 }
226 
TEST(fcntl,tee)227 TEST(fcntl, tee) {
228   char expected[BUFSIZ];
229   FILE* expected_fp = fopen("/proc/version", "r");
230   ASSERT_TRUE(expected_fp != nullptr);
231   ASSERT_TRUE(fgets(expected, sizeof(expected), expected_fp) != nullptr);
232   fclose(expected_fp);
233 
234   int pipe1[2];
235   ASSERT_EQ(0, pipe(pipe1));
236 
237   int pipe2[2];
238   ASSERT_EQ(0, pipe(pipe2));
239 
240   int in = open("/proc/version", O_RDONLY);
241   ASSERT_NE(in, -1);
242 
243   // Write /proc/version into pipe1.
244   ssize_t bytes_read = splice(in, nullptr, pipe1[1], nullptr, 8*1024, SPLICE_F_MORE | SPLICE_F_MOVE);
245   ASSERT_NE(bytes_read, -1);
246   close(pipe1[1]);
247 
248   // Tee /proc/version from pipe1 into pipe2.
249   ssize_t bytes_teed = tee(pipe1[0], pipe2[1], SIZE_MAX, 0);
250   ASSERT_EQ(bytes_read, bytes_teed);
251   close(pipe2[1]);
252 
253   // The out fds of both pipe1 and pipe2 should now contain /proc/version.
254   char buf1[BUFSIZ];
255   FILE* fp1 = fdopen(pipe1[0], "r");
256   ASSERT_TRUE(fp1 != nullptr);
257   ASSERT_TRUE(fgets(buf1, sizeof(buf1), fp1) != nullptr);
258   fclose(fp1);
259 
260   char buf2[BUFSIZ];
261   FILE* fp2 = fdopen(pipe2[0], "r");
262   ASSERT_TRUE(fp2 != nullptr);
263   ASSERT_TRUE(fgets(buf2, sizeof(buf2), fp2) != nullptr);
264   fclose(fp2);
265 
266   ASSERT_STREQ(expected, buf1);
267   ASSERT_STREQ(expected, buf2);
268 }
269 
TEST(fcntl,readahead)270 TEST(fcntl, readahead) {
271   // Just check that the function is available.
272   errno = 0;
273   ASSERT_EQ(-1, readahead(-1, 0, 123));
274   ASSERT_ERRNO(EBADF);
275 }
276 
TEST(fcntl,sync_file_range)277 TEST(fcntl, sync_file_range) {
278   // Just check that the function is available.
279   errno = 0;
280   ASSERT_EQ(-1, sync_file_range(-1, 0, 0, 0));
281   ASSERT_ERRNO(EBADF);
282 
283   TemporaryFile tf;
284   ASSERT_EQ(0, sync_file_range(tf.fd, 0, 0, 0));
285 
286   // The arguments to the underlying system call are in a different order on 32-bit ARM.
287   // Check that the `flags` argument gets passed to the kernel correctly.
288   errno = 0;
289   ASSERT_EQ(-1, sync_file_range(tf.fd, 0, 0, ~0));
290   ASSERT_ERRNO(EINVAL);
291 }
292 
parse_kernel_release(long * const major,long * const minor)293 static bool parse_kernel_release(long* const major, long* const minor) {
294   struct utsname buf;
295   if (uname(&buf) == -1) {
296     return false;
297   }
298   return sscanf(buf.release, "%ld.%ld", major, minor) == 2;
299 }
300 
301 /*
302  * b/28760453:
303  * Kernels older than 4.1 should have ext4 FALLOC_FL_PUNCH_HOLE disabled due to CVE-2015-8839.
304  * Devices that fail this test should cherry-pick the following commit:
305  * https://android.googlesource.com/kernel/msm/+/bdba352e898cbf57c8620ad68c8abf749c784d1f
306  */
TEST(fcntl,falloc_punch)307 TEST(fcntl, falloc_punch) {
308   long major = 0, minor = 0;
309   ASSERT_TRUE(parse_kernel_release(&major, &minor));
310 
311   if (major < 4 || (major == 4 && minor < 1)) {
312     TemporaryFile tf;
313     struct statfs sfs;
314     ASSERT_EQ(0, fstatfs(tf.fd, &sfs));
315     if (sfs.f_type == EXT4_SUPER_MAGIC) {
316       ASSERT_EQ(-1, fallocate(tf.fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, 1));
317       ASSERT_ERRNO(EOPNOTSUPP);
318     }
319   }
320 }
321 
TEST(fcntl,open_O_TMPFILE_mode)322 TEST(fcntl, open_O_TMPFILE_mode) {
323   TemporaryDir dir;
324   // Without O_EXCL, we're allowed to give this a name later.
325   // (This is unrelated to the O_CREAT interaction with O_EXCL.)
326   const mode_t perms = S_IRUSR | S_IWUSR;
327   int fd = open(dir.path, O_TMPFILE | O_RDWR, perms);
328 
329   // Ignore kernels without O_TMPFILE support (< 3.11).
330   if (fd == -1 && (errno == EISDIR || errno == EINVAL || errno == EOPNOTSUPP)) return;
331 
332   ASSERT_TRUE(fd != -1) << strerror(errno);
333 
334   // Does the fd claim to have the mode we set?
335   struct stat sb = {};
336   ASSERT_EQ(0, fstat(fd, &sb));
337   ASSERT_EQ(perms, (sb.st_mode & ~S_IFMT));
338 
339   // On Android if we're not root, we won't be able to create links anyway...
340   if (getuid() != 0) return;
341 
342   std::string final_path = android::base::StringPrintf("%s/named_now", dir.path);
343   ASSERT_EQ(0, linkat(AT_FDCWD, android::base::StringPrintf("/proc/self/fd/%d", fd).c_str(),
344                       AT_FDCWD, final_path.c_str(),
345                       AT_SYMLINK_FOLLOW));
346   ASSERT_EQ(0, close(fd));
347 
348   // Does the resulting file claim to have the mode we set?
349   ASSERT_EQ(0, stat(final_path.c_str(), &sb));
350   ASSERT_EQ(perms, (sb.st_mode & ~S_IFMT));
351 
352   // With O_EXCL, you're not allowed to add a name later.
353   fd = open(dir.path, O_TMPFILE | O_RDWR | O_EXCL, S_IRUSR | S_IWUSR);
354   ASSERT_TRUE(fd != -1) << strerror(errno);
355   errno = 0;
356   ASSERT_EQ(-1, linkat(AT_FDCWD, android::base::StringPrintf("/proc/self/fd/%d", fd).c_str(),
357                        AT_FDCWD, android::base::StringPrintf("%s/no_chance", dir.path).c_str(),
358                        AT_SYMLINK_FOLLOW));
359   ASSERT_ERRNO(ENOENT);
360   ASSERT_EQ(0, close(fd));
361 }
362 
TEST_F(fcntl_DeathTest,fcntl_F_SETFD)363 TEST_F(fcntl_DeathTest, fcntl_F_SETFD) {
364   EXPECT_DEATH(fcntl(0, F_SETFD, O_NONBLOCK), "only supports FD_CLOEXEC");
365 }
366