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1 /*
2  * Copyright (C) 2014 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 <dlfcn.h>
20 #include <elf.h>
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <inttypes.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <unistd.h>
27 
28 #include <android/dlext.h>
29 #include <android-base/strings.h>
30 
31 #include <linux/memfd.h>
32 #include <sys/mman.h>
33 #include <sys/syscall.h>
34 #include <sys/types.h>
35 #include <sys/vfs.h>
36 #include <sys/wait.h>
37 
38 #include <pagemap/pagemap.h>
39 #include <ziparchive/zip_archive.h>
40 
41 #include "gtest_globals.h"
42 #include "TemporaryFile.h"
43 #include "utils.h"
44 #include "dlext_private.h"
45 #include "dlfcn_symlink_support.h"
46 
47 #define ASSERT_DL_NOTNULL(ptr) \
48     ASSERT_TRUE((ptr) != nullptr) << "dlerror: " << dlerror()
49 
50 #define ASSERT_DL_ZERO(i) \
51     ASSERT_EQ(0, i) << "dlerror: " << dlerror()
52 
53 #define ASSERT_NOERROR(i) \
54     ASSERT_NE(-1, i) << "errno: " << strerror(errno)
55 
56 #define ASSERT_SUBSTR(needle, haystack) \
57     ASSERT_PRED_FORMAT2(::testing::IsSubstring, needle, haystack)
58 
59 
60 typedef int (*fn)(void);
61 constexpr const char* kLibName = "libdlext_test.so";
62 constexpr const char* kLibNameNoRelro = "libdlext_test_norelro.so";
63 constexpr const char* kLibZipSimpleZip = "libdir/libatest_simple_zip.so";
64 constexpr auto kLibSize = 1024 * 1024; // how much address space to reserve for it
65 
66 class DlExtTest : public ::testing::Test {
67 protected:
SetUp()68   virtual void SetUp() {
69     handle_ = nullptr;
70     // verify that we don't have the library loaded already
71     void* h = dlopen(kLibName, RTLD_NOW | RTLD_NOLOAD);
72     ASSERT_TRUE(h == nullptr);
73     h = dlopen(kLibNameNoRelro, RTLD_NOW | RTLD_NOLOAD);
74     ASSERT_TRUE(h == nullptr);
75     // call dlerror() to swallow the error, and check it was the one we wanted
76     ASSERT_EQ(std::string("dlopen failed: library \"") + kLibNameNoRelro + "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
77   }
78 
TearDown()79   virtual void TearDown() {
80     if (handle_ != nullptr) {
81       ASSERT_DL_ZERO(dlclose(handle_));
82     }
83   }
84 
85   void* handle_;
86 };
87 
TEST_F(DlExtTest,ExtInfoNull)88 TEST_F(DlExtTest, ExtInfoNull) {
89   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, nullptr);
90   ASSERT_DL_NOTNULL(handle_);
91   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
92   ASSERT_DL_NOTNULL(f);
93   EXPECT_EQ(4, f());
94 }
95 
TEST_F(DlExtTest,ExtInfoNoFlags)96 TEST_F(DlExtTest, ExtInfoNoFlags) {
97   android_dlextinfo extinfo;
98   extinfo.flags = 0;
99   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
100   ASSERT_DL_NOTNULL(handle_);
101   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
102   ASSERT_DL_NOTNULL(f);
103   EXPECT_EQ(4, f());
104 }
105 
TEST_F(DlExtTest,ExtInfoUseFd)106 TEST_F(DlExtTest, ExtInfoUseFd) {
107   const std::string lib_path = get_testlib_root() + "/libdlext_test_fd/libdlext_test_fd.so";
108 
109   android_dlextinfo extinfo;
110   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD;
111   extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
112   ASSERT_TRUE(extinfo.library_fd != -1);
113   handle_ = android_dlopen_ext(lib_path.c_str(), RTLD_NOW, &extinfo);
114   ASSERT_DL_NOTNULL(handle_);
115   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
116   ASSERT_DL_NOTNULL(f);
117   EXPECT_EQ(4, f());
118 
119   uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
120   ASSERT_DL_NOTNULL(taxicab_number);
121   EXPECT_EQ(1729U, *taxicab_number);
122 }
123 
TEST_F(DlExtTest,ExtInfoUseFdWithOffset)124 TEST_F(DlExtTest, ExtInfoUseFdWithOffset) {
125   const std::string lib_path = get_testlib_root() + "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip";
126 
127   android_dlextinfo extinfo;
128   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
129   extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
130 
131   // Find the offset of the shared library in the zip.
132   ZipArchiveHandle handle;
133   ASSERT_EQ(0, OpenArchive(lib_path.c_str(), &handle));
134   ZipEntry zip_entry;
135   ZipString zip_name;
136   zip_name.name = reinterpret_cast<const uint8_t*>(kLibZipSimpleZip);
137   zip_name.name_length = strlen(kLibZipSimpleZip);
138   ASSERT_EQ(0, FindEntry(handle, zip_name, &zip_entry));
139   extinfo.library_fd_offset = zip_entry.offset;
140   CloseArchive(handle);
141 
142   handle_ = android_dlopen_ext(lib_path.c_str(), RTLD_NOW, &extinfo);
143   ASSERT_DL_NOTNULL(handle_);
144 
145   uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
146   ASSERT_DL_NOTNULL(taxicab_number);
147   EXPECT_EQ(1729U, *taxicab_number);
148 }
149 
TEST_F(DlExtTest,ExtInfoUseFdWithInvalidOffset)150 TEST_F(DlExtTest, ExtInfoUseFdWithInvalidOffset) {
151   const std::string lib_path = get_testlib_root() + "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip";
152 
153   android_dlextinfo extinfo;
154   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
155   extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
156   extinfo.library_fd_offset = 17;
157 
158   handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
159   ASSERT_TRUE(handle_ == nullptr);
160   ASSERT_STREQ("dlopen failed: file offset for the library \"libname_placeholder\" is not page-aligned: 17", dlerror());
161 
162   // Test an address above 2^44, for http://b/18178121 .
163   extinfo.library_fd_offset = (5LL<<48) + PAGE_SIZE;
164   handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
165   ASSERT_TRUE(handle_ == nullptr);
166   ASSERT_SUBSTR("dlopen failed: file offset for the library \"libname_placeholder\" >= file size", dlerror());
167 
168   extinfo.library_fd_offset = 0LL - PAGE_SIZE;
169   handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
170   ASSERT_TRUE(handle_ == nullptr);
171   ASSERT_SUBSTR("dlopen failed: file offset for the library \"libname_placeholder\" is negative", dlerror());
172 
173   extinfo.library_fd_offset = 0;
174   handle_ = android_dlopen_ext("libname_ignored", RTLD_NOW, &extinfo);
175   ASSERT_TRUE(handle_ == nullptr);
176   ASSERT_EQ("dlopen failed: \"" + lib_path + "\" has bad ELF magic", dlerror());
177 
178   // Check if dlsym works after unsuccessful dlopen().
179   // Supply non-exiting one to make linker visit every soinfo.
180   void* sym = dlsym(RTLD_DEFAULT, "this_symbol_does_not_exist___");
181   ASSERT_TRUE(sym == nullptr);
182 
183   close(extinfo.library_fd);
184 }
185 
TEST_F(DlExtTest,ExtInfoUseOffsetWithoutFd)186 TEST_F(DlExtTest, ExtInfoUseOffsetWithoutFd) {
187   android_dlextinfo extinfo;
188   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
189   // This offset will not be used, so it doesn't matter.
190   extinfo.library_fd_offset = 0;
191 
192   handle_ = android_dlopen_ext("/some/lib/that/does_not_exist", RTLD_NOW, &extinfo);
193   ASSERT_TRUE(handle_ == nullptr);
194   ASSERT_STREQ("dlopen failed: invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without ANDROID_DLEXT_USE_LIBRARY_FD): 0x20", dlerror());
195 }
196 
TEST(dlext,android_dlopen_ext_force_load_smoke)197 TEST(dlext, android_dlopen_ext_force_load_smoke) {
198   DlfcnSymlink symlink("android_dlopen_ext_force_load_smoke");
199   const std::string symlink_name = basename(symlink.get_symlink_path().c_str());
200   // 1. Open actual file
201   void* handle = dlopen("libdlext_test.so", RTLD_NOW);
202   ASSERT_DL_NOTNULL(handle);
203   // 2. Open link with force_load flag set
204   android_dlextinfo extinfo;
205   extinfo.flags = ANDROID_DLEXT_FORCE_LOAD;
206   void* handle2 = android_dlopen_ext(symlink_name.c_str(), RTLD_NOW, &extinfo);
207   ASSERT_DL_NOTNULL(handle2);
208   ASSERT_TRUE(handle != handle2);
209 
210   dlclose(handle2);
211   dlclose(handle);
212 }
213 
TEST(dlext,android_dlopen_ext_force_load_soname_exception)214 TEST(dlext, android_dlopen_ext_force_load_soname_exception) {
215   DlfcnSymlink symlink("android_dlopen_ext_force_load_soname_exception");
216   const std::string symlink_name = basename(symlink.get_symlink_path().c_str());
217   // Check if soname lookup still returns already loaded library
218   // when ANDROID_DLEXT_FORCE_LOAD flag is specified.
219   void* handle = dlopen(symlink_name.c_str(), RTLD_NOW);
220   ASSERT_DL_NOTNULL(handle);
221 
222   android_dlextinfo extinfo;
223   extinfo.flags = ANDROID_DLEXT_FORCE_LOAD;
224 
225   // Note that 'libdlext_test.so' is dt_soname for the symlink_name
226   void* handle2 = android_dlopen_ext("libdlext_test.so", RTLD_NOW, &extinfo);
227 
228   ASSERT_DL_NOTNULL(handle2);
229   ASSERT_TRUE(handle == handle2);
230 
231   dlclose(handle2);
232   dlclose(handle);
233 }
234 
TEST(dlfcn,dlopen_from_zip_absolute_path)235 TEST(dlfcn, dlopen_from_zip_absolute_path) {
236   const std::string lib_zip_path = "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip";
237   const std::string lib_path = get_testlib_root() + lib_zip_path;
238 
239   void* handle = dlopen((lib_path + "!/libdir/libatest_simple_zip.so").c_str(), RTLD_NOW);
240   ASSERT_TRUE(handle != nullptr) << dlerror();
241 
242   uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
243   ASSERT_DL_NOTNULL(taxicab_number);
244   EXPECT_EQ(1729U, *taxicab_number);
245 
246   dlclose(handle);
247 }
248 
TEST(dlfcn,dlopen_from_zip_with_dt_runpath)249 TEST(dlfcn, dlopen_from_zip_with_dt_runpath) {
250   const std::string lib_zip_path = "/libdlext_test_runpath_zip/libdlext_test_runpath_zip_zipaligned.zip";
251   const std::string lib_path = get_testlib_root() + lib_zip_path;
252 
253   void* handle = dlopen((lib_path + "!/libdir/libtest_dt_runpath_d_zip.so").c_str(), RTLD_NOW);
254 
255   ASSERT_TRUE(handle != nullptr) << dlerror();
256 
257   typedef void *(* dlopen_b_fn)();
258   dlopen_b_fn fn = (dlopen_b_fn)dlsym(handle, "dlopen_b");
259   ASSERT_TRUE(fn != nullptr) << dlerror();
260 
261   void *p = fn();
262   ASSERT_TRUE(p != nullptr) << dlerror();
263 
264   dlclose(p);
265   dlclose(handle);
266 }
267 
TEST(dlfcn,dlopen_from_zip_ld_library_path)268 TEST(dlfcn, dlopen_from_zip_ld_library_path) {
269   const std::string lib_zip_path = "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip";
270   const std::string lib_path = get_testlib_root() + lib_zip_path + "!/libdir";
271 
272   typedef void (*fn_t)(const char*);
273   fn_t android_update_LD_LIBRARY_PATH =
274       reinterpret_cast<fn_t>(dlsym(RTLD_DEFAULT, "android_update_LD_LIBRARY_PATH"));
275 
276   ASSERT_TRUE(android_update_LD_LIBRARY_PATH != nullptr) << dlerror();
277 
278   void* handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
279   ASSERT_TRUE(handle == nullptr);
280 
281   android_update_LD_LIBRARY_PATH(lib_path.c_str());
282 
283   handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
284   ASSERT_TRUE(handle != nullptr) << dlerror();
285 
286   int (*fn)(void);
287   fn = reinterpret_cast<int (*)(void)>(dlsym(handle, "getRandomNumber"));
288   ASSERT_TRUE(fn != nullptr);
289   EXPECT_EQ(4, fn());
290 
291   uint32_t* taxicab_number =
292           reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
293   ASSERT_DL_NOTNULL(taxicab_number);
294   EXPECT_EQ(1729U, *taxicab_number);
295 
296   dlclose(handle);
297 }
298 
299 
TEST_F(DlExtTest,Reserved)300 TEST_F(DlExtTest, Reserved) {
301   void* start = mmap(nullptr, kLibSize, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
302   ASSERT_TRUE(start != MAP_FAILED);
303   android_dlextinfo extinfo;
304   extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
305   extinfo.reserved_addr = start;
306   extinfo.reserved_size = kLibSize;
307   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
308   ASSERT_DL_NOTNULL(handle_);
309   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
310   ASSERT_DL_NOTNULL(f);
311   EXPECT_GE(reinterpret_cast<void*>(f), start);
312   EXPECT_LT(reinterpret_cast<void*>(f),
313             reinterpret_cast<char*>(start) + kLibSize);
314   EXPECT_EQ(4, f());
315 
316   // Check that after dlclose reserved address space is unmapped (and can be reused)
317   dlclose(handle_);
318   handle_ = nullptr;
319 
320   void* new_start = mmap(start, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
321   ASSERT_NE(start, new_start) << "dlclose unmapped reserved space";
322 }
323 
TEST_F(DlExtTest,ReservedTooSmall)324 TEST_F(DlExtTest, ReservedTooSmall) {
325   void* start = mmap(nullptr, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
326   ASSERT_TRUE(start != MAP_FAILED);
327   android_dlextinfo extinfo;
328   extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
329   extinfo.reserved_addr = start;
330   extinfo.reserved_size = PAGE_SIZE;
331   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
332   EXPECT_EQ(nullptr, handle_);
333 }
334 
TEST_F(DlExtTest,ReservedHint)335 TEST_F(DlExtTest, ReservedHint) {
336   void* start = mmap(nullptr, kLibSize, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
337   ASSERT_TRUE(start != MAP_FAILED);
338   android_dlextinfo extinfo;
339   extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
340   extinfo.reserved_addr = start;
341   extinfo.reserved_size = kLibSize;
342   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
343   ASSERT_DL_NOTNULL(handle_);
344   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
345   ASSERT_DL_NOTNULL(f);
346   EXPECT_GE(reinterpret_cast<void*>(f), start);
347   EXPECT_LT(reinterpret_cast<void*>(f),
348             reinterpret_cast<char*>(start) + kLibSize);
349   EXPECT_EQ(4, f());
350 }
351 
TEST_F(DlExtTest,ReservedHintTooSmall)352 TEST_F(DlExtTest, ReservedHintTooSmall) {
353   void* start = mmap(nullptr, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
354   ASSERT_TRUE(start != MAP_FAILED);
355   android_dlextinfo extinfo;
356   extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
357   extinfo.reserved_addr = start;
358   extinfo.reserved_size = PAGE_SIZE;
359   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
360   ASSERT_DL_NOTNULL(handle_);
361   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
362   ASSERT_DL_NOTNULL(f);
363   EXPECT_TRUE(reinterpret_cast<void*>(f) < start ||
364               (reinterpret_cast<void*>(f) >=
365                reinterpret_cast<char*>(start) + PAGE_SIZE));
366   EXPECT_EQ(4, f());
367 }
368 
TEST_F(DlExtTest,LoadAtFixedAddress)369 TEST_F(DlExtTest, LoadAtFixedAddress) {
370   void* start = mmap(nullptr, kLibSize, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
371   ASSERT_TRUE(start != MAP_FAILED);
372   munmap(start, kLibSize);
373 
374   android_dlextinfo extinfo;
375   extinfo.flags = ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS;
376   extinfo.reserved_addr = start;
377 
378   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
379   ASSERT_DL_NOTNULL(handle_);
380   fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
381   ASSERT_DL_NOTNULL(f);
382   EXPECT_GE(reinterpret_cast<void*>(f), start);
383   EXPECT_LT(reinterpret_cast<void*>(f), reinterpret_cast<char*>(start) + kLibSize);
384 
385   EXPECT_EQ(4, f());
386   dlclose(handle_);
387   handle_ = nullptr;
388 
389   // Check that dlclose unmapped the file
390   void* addr = mmap(start, kLibSize, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
391   ASSERT_EQ(start, addr) << "dlclose did not unmap the memory";
392 }
393 
TEST_F(DlExtTest,LoadAtFixedAddressTooSmall)394 TEST_F(DlExtTest, LoadAtFixedAddressTooSmall) {
395   void* start = mmap(nullptr, kLibSize + PAGE_SIZE, PROT_NONE,
396                          MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
397   ASSERT_TRUE(start != MAP_FAILED);
398   munmap(start, kLibSize + PAGE_SIZE);
399   void* new_addr = mmap(reinterpret_cast<uint8_t*>(start) + PAGE_SIZE, kLibSize, PROT_NONE,
400                         MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
401   ASSERT_TRUE(new_addr != MAP_FAILED);
402 
403   android_dlextinfo extinfo;
404   extinfo.flags = ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS;
405   extinfo.reserved_addr = start;
406 
407   handle_ = android_dlopen_ext(kLibName, RTLD_NOW, &extinfo);
408   ASSERT_TRUE(handle_ == nullptr);
409 }
410 
411 class DlExtRelroSharingTest : public DlExtTest {
412 protected:
SetUp()413   virtual void SetUp() {
414     DlExtTest::SetUp();
415     void* start = mmap(nullptr, kLibSize, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
416     ASSERT_TRUE(start != MAP_FAILED);
417     extinfo_.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
418     extinfo_.reserved_addr = start;
419     extinfo_.reserved_size = kLibSize;
420     extinfo_.relro_fd = -1;
421   }
422 
TearDown()423   virtual void TearDown() {
424     DlExtTest::TearDown();
425   }
426 
CreateRelroFile(const char * lib,const char * relro_file)427   void CreateRelroFile(const char* lib, const char* relro_file) {
428     int relro_fd = open(relro_file, O_RDWR | O_TRUNC);
429     ASSERT_NOERROR(relro_fd);
430 
431     pid_t pid = fork();
432     if (pid == 0) {
433       // child process
434       extinfo_.flags |= ANDROID_DLEXT_WRITE_RELRO;
435       extinfo_.relro_fd = relro_fd;
436       void* handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
437       if (handle == nullptr) {
438         fprintf(stderr, "in child: %s\n", dlerror());
439         exit(1);
440       }
441       exit(0);
442     }
443 
444     // continuing in parent
445     ASSERT_NOERROR(close(relro_fd));
446     ASSERT_NOERROR(pid);
447     AssertChildExited(pid, 0);
448 
449     // reopen file for reading so it can be used
450     relro_fd = open(relro_file, O_RDONLY);
451     ASSERT_NOERROR(relro_fd);
452     extinfo_.flags |= ANDROID_DLEXT_USE_RELRO;
453     extinfo_.relro_fd = relro_fd;
454   }
455 
TryUsingRelro(const char * lib)456   void TryUsingRelro(const char* lib) {
457     handle_ = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
458     ASSERT_DL_NOTNULL(handle_);
459     fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
460     ASSERT_DL_NOTNULL(f);
461     EXPECT_EQ(4, f());
462 
463     uint32_t* taxicab_number =
464             reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
465     ASSERT_DL_NOTNULL(taxicab_number);
466     EXPECT_EQ(1729U, *taxicab_number);
467   }
468 
469   void SpawnChildrenAndMeasurePss(const char* lib, const char* relro_file, bool share_relro,
470                                   size_t* pss_out);
471 
472   android_dlextinfo extinfo_;
473 };
474 
TEST_F(DlExtRelroSharingTest,ChildWritesGoodData)475 TEST_F(DlExtRelroSharingTest, ChildWritesGoodData) {
476   TemporaryFile tf; // Use tf to get an unique filename.
477   ASSERT_NOERROR(close(tf.fd));
478 
479   ASSERT_NO_FATAL_FAILURE(CreateRelroFile(kLibName, tf.filename));
480   ASSERT_NO_FATAL_FAILURE(TryUsingRelro(kLibName));
481 
482   // Use destructor of tf to close and unlink the file.
483   tf.fd = extinfo_.relro_fd;
484 }
485 
TEST_F(DlExtRelroSharingTest,ChildWritesNoRelro)486 TEST_F(DlExtRelroSharingTest, ChildWritesNoRelro) {
487   TemporaryFile tf; // // Use tf to get an unique filename.
488   ASSERT_NOERROR(close(tf.fd));
489 
490   ASSERT_NO_FATAL_FAILURE(CreateRelroFile(kLibNameNoRelro, tf.filename));
491   ASSERT_NO_FATAL_FAILURE(TryUsingRelro(kLibNameNoRelro));
492 
493   // Use destructor of tf to close and unlink the file.
494   tf.fd = extinfo_.relro_fd;
495 }
496 
TEST_F(DlExtRelroSharingTest,RelroFileEmpty)497 TEST_F(DlExtRelroSharingTest, RelroFileEmpty) {
498   ASSERT_NO_FATAL_FAILURE(TryUsingRelro(kLibName));
499 }
500 
TEST_F(DlExtRelroSharingTest,VerifyMemorySaving)501 TEST_F(DlExtRelroSharingTest, VerifyMemorySaving) {
502   if (geteuid() != 0) {
503     GTEST_LOG_(INFO) << "This test must be run as root.\n";
504     return;
505   }
506 
507   TemporaryFile tf; // Use tf to get an unique filename.
508   ASSERT_NOERROR(close(tf.fd));
509 
510   ASSERT_NO_FATAL_FAILURE(CreateRelroFile(kLibName, tf.filename));
511 
512   int pipefd[2];
513   ASSERT_NOERROR(pipe(pipefd));
514 
515   size_t without_sharing, with_sharing;
516   ASSERT_NO_FATAL_FAILURE(SpawnChildrenAndMeasurePss(kLibName, tf.filename, false, &without_sharing));
517   ASSERT_NO_FATAL_FAILURE(SpawnChildrenAndMeasurePss(kLibName, tf.filename, true, &with_sharing));
518   ASSERT_LT(with_sharing, without_sharing);
519 
520   // We expect the sharing to save at least 50% of the library's total PSS.
521   // In practice it saves 80%+ for this library in the test.
522   size_t pss_saved = without_sharing - with_sharing;
523   size_t expected_min_saved = without_sharing / 2;
524 
525   EXPECT_LT(expected_min_saved, pss_saved);
526 
527   // Use destructor of tf to close and unlink the file.
528   tf.fd = extinfo_.relro_fd;
529 }
530 
GetPss(bool shared_relro,const char * lib,const char * relro_file,pid_t pid,size_t * total_pss)531 void GetPss(bool shared_relro, const char* lib, const char* relro_file, pid_t pid,
532             size_t* total_pss) {
533   pm_kernel_t* kernel;
534   ASSERT_EQ(0, pm_kernel_create(&kernel));
535 
536   pm_process_t* process;
537   ASSERT_EQ(0, pm_process_create(kernel, pid, &process));
538 
539   pm_map_t** maps;
540   size_t num_maps;
541   ASSERT_EQ(0, pm_process_maps(process, &maps, &num_maps));
542 
543   // Calculate total PSS of the library.
544   *total_pss = 0;
545   bool saw_relro_file = false;
546   for (size_t i = 0; i < num_maps; ++i) {
547     if (android::base::EndsWith(maps[i]->name, lib) || strcmp(maps[i]->name, relro_file) == 0) {
548       if (strcmp(maps[i]->name, relro_file) == 0) saw_relro_file = true;
549 
550       pm_memusage_t usage;
551       ASSERT_EQ(0, pm_map_usage(maps[i], &usage));
552       *total_pss += usage.pss;
553     }
554   }
555 
556   free(maps);
557   pm_process_destroy(process);
558   pm_kernel_destroy(kernel);
559 
560   if (shared_relro) ASSERT_TRUE(saw_relro_file);
561 }
562 
SpawnChildrenAndMeasurePss(const char * lib,const char * relro_file,bool share_relro,size_t * pss_out)563 void DlExtRelroSharingTest::SpawnChildrenAndMeasurePss(const char* lib, const char* relro_file,
564                                                        bool share_relro, size_t* pss_out) {
565   const int CHILDREN = 20;
566 
567   // Create children
568   pid_t child_pids[CHILDREN];
569   int childpipe[CHILDREN];
570   for (int i=0; i<CHILDREN; ++i) {
571     char read_buf;
572     int child_done_pipe[2], parent_done_pipe[2];
573     ASSERT_NOERROR(pipe(child_done_pipe));
574     ASSERT_NOERROR(pipe(parent_done_pipe));
575 
576     pid_t child = fork();
577     if (child == 0) {
578       // close the 'wrong' ends of the pipes in the child
579       close(child_done_pipe[0]);
580       close(parent_done_pipe[1]);
581 
582       // open the library
583       void* handle;
584       if (share_relro) {
585         handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
586       } else {
587         handle = dlopen(lib, RTLD_NOW);
588       }
589       if (handle == nullptr) {
590         fprintf(stderr, "in child: %s\n", dlerror());
591         exit(1);
592       }
593 
594       // close write end of child_done_pipe to signal the parent that we're done.
595       close(child_done_pipe[1]);
596 
597       // wait for the parent to close parent_done_pipe, then exit
598       read(parent_done_pipe[0], &read_buf, 1);
599       exit(0);
600     }
601 
602     ASSERT_NOERROR(child);
603 
604     // close the 'wrong' ends of the pipes in the parent
605     close(child_done_pipe[1]);
606     close(parent_done_pipe[0]);
607 
608     // wait for the child to be done
609     read(child_done_pipe[0], &read_buf, 1);
610     close(child_done_pipe[0]);
611 
612     // save the child's pid and the parent_done_pipe
613     child_pids[i] = child;
614     childpipe[i] = parent_done_pipe[1];
615   }
616 
617   // Sum the PSS of tested library of all the children
618   size_t total_pss = 0;
619   for (int i=0; i<CHILDREN; ++i) {
620     size_t child_pss;
621     ASSERT_NO_FATAL_FAILURE(GetPss(share_relro, lib, relro_file, child_pids[i], &child_pss));
622     total_pss += child_pss;
623   }
624   *pss_out = total_pss;
625 
626   // Close pipes and wait for children to exit
627   for (int i=0; i<CHILDREN; ++i) {
628     ASSERT_NOERROR(close(childpipe[i]));
629   }
630   for (int i = 0; i < CHILDREN; ++i) {
631     AssertChildExited(child_pids[i], 0);
632   }
633 }
634 
635 // Testing namespaces
636 static const char* g_public_lib = "libnstest_public.so";
637 
638 // These are libs shared with default namespace
639 static const std::string g_core_shared_libs = "libc.so:libc++.so:libdl.so:libm.so";
640 
TEST(dlext,ns_smoke)641 TEST(dlext, ns_smoke) {
642   static const char* root_lib = "libnstest_root.so";
643   std::string shared_libs = g_core_shared_libs + ":" + g_public_lib;
644 
645   ASSERT_FALSE(android_init_anonymous_namespace("", nullptr));
646   ASSERT_STREQ("android_init_anonymous_namespace failed: error linking namespaces"
647                " \"(anonymous)\"->\"(default)\": the list of shared libraries is empty.",
648                dlerror());
649 
650   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs/" + g_public_lib;
651   void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
652   ASSERT_TRUE(handle_public != nullptr) << dlerror();
653 
654   ASSERT_TRUE(android_init_anonymous_namespace(shared_libs.c_str(), nullptr)) << dlerror();
655 
656   // Check that libraries added to public namespace are not NODELETE
657   dlclose(handle_public);
658   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW | RTLD_NOLOAD);
659   ASSERT_TRUE(handle_public == nullptr);
660   ASSERT_EQ(std::string("dlopen failed: library \"") + lib_public_path +
661                "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
662 
663   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
664 
665   // create "public namespace", share limited set of public libraries with
666 
667   android_namespace_t* ns1 =
668           android_create_namespace("private",
669                                    nullptr,
670                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
671                                    ANDROID_NAMESPACE_TYPE_REGULAR,
672                                    nullptr,
673                                    nullptr);
674   ASSERT_TRUE(ns1 != nullptr) << dlerror();
675   ASSERT_TRUE(android_link_namespaces(ns1, nullptr, shared_libs.c_str())) << dlerror();
676 
677   android_namespace_t* ns2 =
678           android_create_namespace("private_isolated",
679                                    nullptr,
680                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
681                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
682                                    nullptr,
683                                    nullptr);
684   ASSERT_TRUE(ns2 != nullptr) << dlerror();
685   ASSERT_TRUE(android_link_namespaces(ns2, nullptr, shared_libs.c_str())) << dlerror();
686 
687   // This should not have affect search path for default namespace:
688   ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
689   void* handle = dlopen(g_public_lib, RTLD_NOW);
690   ASSERT_TRUE(handle != nullptr) << dlerror();
691   dlclose(handle);
692 
693   // dlopen for a public library using an absolute path should work
694   // 1. For isolated namespaces
695   android_dlextinfo extinfo;
696   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
697   extinfo.library_namespace = ns2;
698   handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
699   ASSERT_TRUE(handle != nullptr) << dlerror();
700   ASSERT_TRUE(handle == handle_public);
701 
702   dlclose(handle);
703 
704   // 1.1 even if it wasn't loaded before
705   dlclose(handle_public);
706 
707   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW | RTLD_NOLOAD);
708   ASSERT_TRUE(handle_public == nullptr);
709   ASSERT_EQ(std::string("dlopen failed: library \"") + lib_public_path +
710                "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
711 
712   handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
713   ASSERT_TRUE(handle != nullptr) << dlerror();
714 
715   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
716   ASSERT_TRUE(handle == handle_public);
717 
718   dlclose(handle);
719 
720   // 2. And for regular namespaces (make sure it does not load second copy of the library)
721   extinfo.library_namespace = ns1;
722   handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
723   ASSERT_TRUE(handle != nullptr) << dlerror();
724   ASSERT_TRUE(handle == handle_public);
725 
726   dlclose(handle);
727 
728   // 2.1 Unless it was not loaded before - in which case it will load a duplicate.
729   // TODO(dimitry): This is broken. Maybe we need to deprecate non-isolated namespaces?
730   dlclose(handle_public);
731 
732   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW | RTLD_NOLOAD);
733   ASSERT_TRUE(handle_public == nullptr);
734   ASSERT_EQ(std::string("dlopen failed: library \"") + lib_public_path +
735                "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
736 
737   handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
738   ASSERT_TRUE(handle != nullptr) << dlerror();
739 
740   handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
741 
742   ASSERT_TRUE(handle != handle_public);
743 
744   dlclose(handle);
745 
746   extinfo.library_namespace = ns1;
747 
748   void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
749   ASSERT_TRUE(handle1 != nullptr) << dlerror();
750 
751   extinfo.library_namespace = ns2;
752   void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
753   ASSERT_TRUE(handle2 != nullptr) << dlerror();
754 
755   ASSERT_TRUE(handle1 != handle2);
756 
757   typedef const char* (*fn_t)();
758 
759   fn_t ns_get_local_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
760   ASSERT_TRUE(ns_get_local_string1 != nullptr) << dlerror();
761   fn_t ns_get_local_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_local_string"));
762   ASSERT_TRUE(ns_get_local_string2 != nullptr) << dlerror();
763 
764   EXPECT_STREQ("This string is local to root library", ns_get_local_string1());
765   EXPECT_STREQ("This string is local to root library", ns_get_local_string2());
766 
767   ASSERT_TRUE(ns_get_local_string1() != ns_get_local_string2());
768 
769   fn_t ns_get_private_extern_string1 =
770           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
771   ASSERT_TRUE(ns_get_private_extern_string1 != nullptr) << dlerror();
772   fn_t ns_get_private_extern_string2 =
773           reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_private_extern_string"));
774   ASSERT_TRUE(ns_get_private_extern_string2 != nullptr) << dlerror();
775 
776   EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string1());
777   EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
778 
779   ASSERT_TRUE(ns_get_private_extern_string1() != ns_get_private_extern_string2());
780 
781   fn_t ns_get_public_extern_string1 =
782           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
783   ASSERT_TRUE(ns_get_public_extern_string1 != nullptr) << dlerror();
784   fn_t ns_get_public_extern_string2 =
785           reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_public_extern_string"));
786   ASSERT_TRUE(ns_get_public_extern_string2 != nullptr) << dlerror();
787 
788   EXPECT_STREQ("This string is from public namespace", ns_get_public_extern_string1());
789   ASSERT_TRUE(ns_get_public_extern_string1() == ns_get_public_extern_string2());
790 
791   // and now check that dlopen() does the right thing in terms of preserving namespace
792   fn_t ns_get_dlopened_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
793   ASSERT_TRUE(ns_get_dlopened_string1 != nullptr) << dlerror();
794   fn_t ns_get_dlopened_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_dlopened_string"));
795   ASSERT_TRUE(ns_get_dlopened_string2 != nullptr) << dlerror();
796 
797   EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string1());
798   EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
799 
800   ASSERT_TRUE(ns_get_dlopened_string1() != ns_get_dlopened_string2());
801 
802   // Check that symbols from non-shared libraries a shared library depends on are not visible
803   // from original namespace.
804 
805   fn_t ns_get_internal_extern_string =
806           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_internal_extern_string"));
807   ASSERT_TRUE(ns_get_internal_extern_string != nullptr) << dlerror();
808   ASSERT_TRUE(ns_get_internal_extern_string() == nullptr) <<
809       "ns_get_internal_extern_string() expected to return null but returns \"" <<
810       ns_get_internal_extern_string() << "\"";
811 
812   dlclose(handle1);
813 
814   // Check if handle2 is still alive (and well)
815   ASSERT_STREQ("This string is local to root library", ns_get_local_string2());
816   ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
817   ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string2());
818   ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
819 
820   dlclose(handle2);
821 }
822 
TEST(dlext,dlopen_ext_use_o_tmpfile_fd)823 TEST(dlext, dlopen_ext_use_o_tmpfile_fd) {
824   const std::string lib_path = get_testlib_root() + "/libtest_simple.so";
825 
826   int tmpfd = TEMP_FAILURE_RETRY(
827         open(get_testlib_root().c_str(), O_TMPFILE | O_CLOEXEC | O_RDWR | O_EXCL));
828 
829   // Ignore kernels without O_TMPFILE flag support
830   if (tmpfd == -1 && (errno == EISDIR || errno == EINVAL || errno == EOPNOTSUPP)) {
831     return;
832   }
833 
834   ASSERT_TRUE(tmpfd != -1) << strerror(errno);
835 
836   android_namespace_t* ns =
837           android_create_namespace("testing-o_tmpfile",
838                                    nullptr,
839                                    get_testlib_root().c_str(),
840                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
841                                    nullptr,
842                                    nullptr);
843 
844   ASSERT_DL_NOTNULL(ns);
845 
846   ASSERT_TRUE(android_link_namespaces(ns, nullptr, g_core_shared_libs.c_str())) << dlerror();
847 
848   std::string content;
849   ASSERT_TRUE(android::base::ReadFileToString(lib_path, &content)) << strerror(errno);
850   ASSERT_TRUE(android::base::WriteStringToFd(content, tmpfd)) << strerror(errno);
851 
852   android_dlextinfo extinfo;
853   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_NAMESPACE;
854   extinfo.library_fd = tmpfd;
855   extinfo.library_namespace = ns;
856 
857   void* handle = android_dlopen_ext("foobar", RTLD_NOW, &extinfo);
858 
859   ASSERT_DL_NOTNULL(handle);
860 
861   uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
862   ASSERT_DL_NOTNULL(taxicab_number);
863   EXPECT_EQ(1729U, *taxicab_number);
864   dlclose(handle);
865 }
866 
TEST(dlext,dlopen_ext_use_memfd)867 TEST(dlext, dlopen_ext_use_memfd) {
868   const std::string lib_path = get_testlib_root() + "/libtest_simple.so";
869 
870   // create memfd
871   int memfd = syscall(__NR_memfd_create, "foobar", MFD_CLOEXEC);
872   if (memfd == -1 && errno == ENOSYS) {
873     return;
874   }
875 
876   ASSERT_TRUE(memfd != -1) << strerror(errno);
877 
878   // Check st.f_type is TMPFS_MAGIC for memfd
879   struct statfs st;
880   ASSERT_TRUE(TEMP_FAILURE_RETRY(fstatfs(memfd, &st)) == 0) << strerror(errno);
881   ASSERT_EQ(static_cast<decltype(st.f_type)>(TMPFS_MAGIC), st.f_type);
882 
883   android_namespace_t* ns =
884           android_create_namespace("testing-memfd",
885                                    nullptr,
886                                    get_testlib_root().c_str(),
887                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
888                                    nullptr,
889                                    nullptr);
890 
891   ASSERT_DL_NOTNULL(ns);
892 
893   ASSERT_TRUE(android_link_namespaces(ns, nullptr, g_core_shared_libs.c_str())) << dlerror();
894 
895   // read file into memfd backed one.
896   std::string content;
897   ASSERT_TRUE(android::base::ReadFileToString(lib_path, &content)) << strerror(errno);
898   ASSERT_TRUE(android::base::WriteStringToFd(content, memfd)) << strerror(errno);
899 
900   android_dlextinfo extinfo;
901   extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_NAMESPACE;
902   extinfo.library_fd = memfd;
903   extinfo.library_namespace = ns;
904 
905   void* handle = android_dlopen_ext("foobar", RTLD_NOW, &extinfo);
906 
907   ASSERT_DL_NOTNULL(handle);
908 
909   uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
910   ASSERT_DL_NOTNULL(taxicab_number);
911   EXPECT_EQ(1729U, *taxicab_number);
912   dlclose(handle);
913 }
914 
TEST(dlext,ns_symbol_visibilty_one_namespace)915 TEST(dlext, ns_symbol_visibilty_one_namespace) {
916   static const char* root_lib = "libnstest_root.so";
917   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
918 
919   const std::string ns_search_path = get_testlib_root() + "/public_namespace_libs:" +
920                                      get_testlib_root() + "/private_namespace_libs";
921 
922   android_namespace_t* ns =
923           android_create_namespace("one",
924                                    nullptr,
925                                    ns_search_path.c_str(),
926                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
927                                    nullptr,
928                                    nullptr);
929 
930   ASSERT_TRUE(android_link_namespaces(ns, nullptr, g_core_shared_libs.c_str())) << dlerror();
931 
932   android_dlextinfo extinfo;
933   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
934   extinfo.library_namespace = ns;
935 
936   void* handle = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
937   ASSERT_TRUE(handle != nullptr) << dlerror();
938 
939   typedef const char* (*fn_t)();
940 
941   // Check that relocation worked correctly
942   fn_t ns_get_internal_extern_string =
943           reinterpret_cast<fn_t>(dlsym(handle, "ns_get_internal_extern_string"));
944   ASSERT_TRUE(ns_get_internal_extern_string != nullptr) << dlerror();
945   ASSERT_STREQ("This string is from a library a shared library depends on", ns_get_internal_extern_string());
946 
947   fn_t internal_extern_string_fn =
948           reinterpret_cast<fn_t>(dlsym(handle, "internal_extern_string"));
949   ASSERT_TRUE(internal_extern_string_fn != nullptr) << dlerror();
950   ASSERT_STREQ("This string is from a library a shared library depends on", internal_extern_string_fn());
951 }
952 
TEST(dlext,ns_symbol_visibilty_between_namespaces)953 TEST(dlext, ns_symbol_visibilty_between_namespaces) {
954   static const char* root_lib = "libnstest_root.so";
955   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
956 
957   const std::string public_ns_search_path =  get_testlib_root() + "/public_namespace_libs";
958   const std::string private_ns_search_path = get_testlib_root() + "/private_namespace_libs";
959 
960   android_namespace_t* ns_public =
961           android_create_namespace("public",
962                                    nullptr,
963                                    public_ns_search_path.c_str(),
964                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
965                                    nullptr,
966                                    nullptr);
967 
968   ASSERT_TRUE(android_link_namespaces(ns_public, nullptr, g_core_shared_libs.c_str())) << dlerror();
969 
970   android_namespace_t* ns_private =
971           android_create_namespace("private",
972                                    nullptr,
973                                    private_ns_search_path.c_str(),
974                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
975                                    nullptr,
976                                    nullptr);
977 
978   ASSERT_TRUE(android_link_namespaces(ns_private, ns_public, g_public_lib)) << dlerror();
979   ASSERT_TRUE(android_link_namespaces(ns_private, nullptr, g_core_shared_libs.c_str())) << dlerror();
980 
981   android_dlextinfo extinfo;
982   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
983   extinfo.library_namespace = ns_private;
984 
985   void* handle = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
986   ASSERT_TRUE(handle != nullptr) << dlerror();
987 
988   typedef const char* (*fn_t)();
989 
990   // Check that relocation worked correctly
991   fn_t ns_get_internal_extern_string =
992           reinterpret_cast<fn_t>(dlsym(handle, "ns_get_internal_extern_string"));
993   ASSERT_TRUE(ns_get_internal_extern_string != nullptr) << dlerror();
994   ASSERT_TRUE(ns_get_internal_extern_string() == nullptr) <<
995       "ns_get_internal_extern_string() expected to return null but returns \"" <<
996       ns_get_internal_extern_string() << "\"";
997 
998   fn_t internal_extern_string_fn =
999           reinterpret_cast<fn_t>(dlsym(handle, "internal_extern_string"));
1000   ASSERT_TRUE(internal_extern_string_fn == nullptr);
1001   ASSERT_STREQ("undefined symbol: internal_extern_string", dlerror());
1002 }
1003 
TEST(dlext,ns_unload_between_namespaces)1004 TEST(dlext, ns_unload_between_namespaces) {
1005   static const char* root_lib = "libnstest_root.so";
1006   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
1007 
1008   const std::string public_ns_search_path =  get_testlib_root() + "/public_namespace_libs";
1009   const std::string private_ns_search_path = get_testlib_root() + "/private_namespace_libs";
1010 
1011   android_namespace_t* ns_public =
1012           android_create_namespace("public",
1013                                    nullptr,
1014                                    public_ns_search_path.c_str(),
1015                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1016                                    nullptr,
1017                                    nullptr);
1018 
1019   ASSERT_TRUE(android_link_namespaces(ns_public, nullptr, g_core_shared_libs.c_str())) << dlerror();
1020 
1021   android_namespace_t* ns_private =
1022           android_create_namespace("private",
1023                                    nullptr,
1024                                    private_ns_search_path.c_str(),
1025                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1026                                    nullptr,
1027                                    nullptr);
1028 
1029   ASSERT_TRUE(android_link_namespaces(ns_private, ns_public, g_public_lib)) << dlerror();
1030   ASSERT_TRUE(android_link_namespaces(ns_private, nullptr, g_core_shared_libs.c_str())) << dlerror();
1031 
1032   android_dlextinfo extinfo;
1033   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1034   extinfo.library_namespace = ns_private;
1035 
1036   void* handle = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1037   ASSERT_TRUE(handle != nullptr) << dlerror();
1038 
1039   dlclose(handle);
1040   // Check that root_lib was unloaded
1041   handle = android_dlopen_ext(root_lib, RTLD_NOW | RTLD_NOLOAD, &extinfo);
1042   ASSERT_TRUE(handle == nullptr);
1043   ASSERT_EQ(std::string("dlopen failed: library \"") + root_lib +
1044             "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
1045 
1046   // Check that shared library was unloaded in public ns
1047   extinfo.library_namespace = ns_public;
1048   handle = android_dlopen_ext(g_public_lib, RTLD_NOW | RTLD_NOLOAD, &extinfo);
1049   ASSERT_TRUE(handle == nullptr);
1050   ASSERT_EQ(std::string("dlopen failed: library \"") + g_public_lib +
1051             "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
1052 }
1053 
TEST(dlext,ns_greylist_enabled)1054 TEST(dlext, ns_greylist_enabled) {
1055   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
1056 
1057   const std::string ns_search_path = get_testlib_root() + "/private_namespace_libs";
1058 
1059   android_namespace_t* ns =
1060           android_create_namespace("namespace",
1061                                    nullptr,
1062                                    ns_search_path.c_str(),
1063                                    ANDROID_NAMESPACE_TYPE_ISOLATED | ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED,
1064                                    nullptr,
1065                                    nullptr);
1066 
1067   ASSERT_TRUE(android_link_namespaces(ns, nullptr, g_core_shared_libs.c_str())) << dlerror();
1068 
1069   android_dlextinfo extinfo;
1070   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1071   extinfo.library_namespace = ns;
1072 
1073   // An app targeting M can open libnativehelper.so because it's on the greylist.
1074   android_set_application_target_sdk_version(__ANDROID_API_M__);
1075   void* handle = android_dlopen_ext("libnativehelper.so", RTLD_NOW, &extinfo);
1076   ASSERT_TRUE(handle != nullptr) << dlerror();
1077 
1078   // Check that loader did not load another copy of libdl.so while loading greylisted library.
1079   void* dlsym_ptr = dlsym(handle, "dlsym");
1080   ASSERT_TRUE(dlsym_ptr != nullptr) << dlerror();
1081   ASSERT_EQ(&dlsym, dlsym_ptr);
1082 
1083   dlclose(handle);
1084 
1085   // An app targeting N no longer has the greylist.
1086   android_set_application_target_sdk_version(__ANDROID_API_N__);
1087   handle = android_dlopen_ext("libnativehelper.so", RTLD_NOW, &extinfo);
1088   ASSERT_TRUE(handle == nullptr);
1089   ASSERT_STREQ("dlopen failed: library \"libnativehelper.so\" not found", dlerror());
1090 }
1091 
TEST(dlext,ns_greylist_disabled_by_default)1092 TEST(dlext, ns_greylist_disabled_by_default) {
1093   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
1094 
1095   const std::string ns_search_path = get_testlib_root() + "/private_namespace_libs";
1096 
1097   android_namespace_t* ns =
1098           android_create_namespace("namespace",
1099                                    nullptr,
1100                                    ns_search_path.c_str(),
1101                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1102                                    nullptr,
1103                                    nullptr);
1104 
1105   ASSERT_TRUE(android_link_namespaces(ns, nullptr, g_core_shared_libs.c_str())) << dlerror();
1106 
1107   android_dlextinfo extinfo;
1108   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1109   extinfo.library_namespace = ns;
1110 
1111   android_set_application_target_sdk_version(__ANDROID_API_M__);
1112   void* handle = android_dlopen_ext("libnativehelper.so", RTLD_NOW, &extinfo);
1113   ASSERT_TRUE(handle == nullptr);
1114   ASSERT_STREQ("dlopen failed: library \"libnativehelper.so\" not found", dlerror());
1115 }
1116 
TEST(dlext,ns_cyclic_namespaces)1117 TEST(dlext, ns_cyclic_namespaces) {
1118   // Test that ns1->ns2->ns1 link does not break the loader
1119   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
1120   std::string shared_libs = g_core_shared_libs + ":libthatdoesnotexist.so";
1121 
1122   const std::string ns_search_path =  get_testlib_root() + "/public_namespace_libs";
1123 
1124   android_namespace_t* ns1 =
1125           android_create_namespace("ns1",
1126                                    nullptr,
1127                                    ns_search_path.c_str(),
1128                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1129                                    nullptr,
1130                                    nullptr);
1131 
1132   ASSERT_TRUE(android_link_namespaces(ns1, nullptr, g_core_shared_libs.c_str())) << dlerror();
1133 
1134   android_namespace_t* ns2 =
1135           android_create_namespace("ns1",
1136                                    nullptr,
1137                                    ns_search_path.c_str(),
1138                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1139                                    nullptr,
1140                                    nullptr);
1141 
1142   ASSERT_TRUE(android_link_namespaces(ns2, nullptr, g_core_shared_libs.c_str())) << dlerror();
1143 
1144   ASSERT_TRUE(android_link_namespaces(ns2, ns1, shared_libs.c_str())) << dlerror();
1145   ASSERT_TRUE(android_link_namespaces(ns1, ns2, shared_libs.c_str())) << dlerror();
1146 
1147   android_dlextinfo extinfo;
1148   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1149   extinfo.library_namespace = ns1;
1150 
1151   void* handle = android_dlopen_ext("libthatdoesnotexist.so", RTLD_NOW, &extinfo);
1152   ASSERT_TRUE(handle == nullptr);
1153   ASSERT_STREQ("dlopen failed: library \"libthatdoesnotexist.so\" not found", dlerror());
1154 }
1155 
TEST(dlext,ns_isolated)1156 TEST(dlext, ns_isolated) {
1157   static const char* root_lib = "libnstest_root_not_isolated.so";
1158   std::string shared_libs = g_core_shared_libs + ":" + g_public_lib;
1159 
1160   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs/" + g_public_lib;
1161   void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
1162   ASSERT_TRUE(handle_public != nullptr) << dlerror();
1163 
1164   android_set_application_target_sdk_version(42U); // something > 23
1165 
1166   ASSERT_TRUE(android_init_anonymous_namespace(shared_libs.c_str(), nullptr)) << dlerror();
1167 
1168   android_namespace_t* ns_not_isolated =
1169           android_create_namespace("private",
1170                                    nullptr,
1171                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1172                                    ANDROID_NAMESPACE_TYPE_REGULAR,
1173                                    nullptr,
1174                                    nullptr);
1175   ASSERT_TRUE(ns_not_isolated != nullptr) << dlerror();
1176   ASSERT_TRUE(android_link_namespaces(ns_not_isolated, nullptr, shared_libs.c_str())) << dlerror();
1177 
1178   android_namespace_t* ns_isolated =
1179           android_create_namespace("private_isolated1",
1180                                    nullptr,
1181                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1182                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1183                                    nullptr,
1184                                    nullptr);
1185   ASSERT_TRUE(ns_isolated != nullptr) << dlerror();
1186   ASSERT_TRUE(android_link_namespaces(ns_isolated, nullptr, shared_libs.c_str())) << dlerror();
1187 
1188   android_namespace_t* ns_isolated2 =
1189           android_create_namespace("private_isolated2",
1190                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1191                                    nullptr,
1192                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1193                                    get_testlib_root().c_str(),
1194                                    nullptr);
1195   ASSERT_TRUE(ns_isolated2 != nullptr) << dlerror();
1196   ASSERT_TRUE(android_link_namespaces(ns_isolated2, nullptr, shared_libs.c_str())) << dlerror();
1197 
1198   ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
1199   ASSERT_STREQ("dlopen failed: library \"libnstest_root_not_isolated.so\" not found", dlerror());
1200 
1201   std::string lib_private_external_path =
1202       get_testlib_root() + "/private_namespace_libs_external/libnstest_private_external.so";
1203 
1204   // Load lib_private_external_path to default namespace
1205   // (it should remain invisible for the isolated namespaces after this)
1206   void* handle = dlopen(lib_private_external_path.c_str(), RTLD_NOW);
1207   ASSERT_TRUE(handle != nullptr) << dlerror();
1208 
1209   android_dlextinfo extinfo;
1210   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1211   extinfo.library_namespace = ns_not_isolated;
1212 
1213   void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1214   ASSERT_TRUE(handle1 != nullptr) << dlerror();
1215 
1216   extinfo.library_namespace = ns_isolated;
1217 
1218   void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1219   ASSERT_TRUE(handle2 == nullptr);
1220   ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());
1221 
1222   // Check dlopen by absolute path
1223   handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
1224   ASSERT_TRUE(handle2 == nullptr);
1225   ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" needed"
1226             " or dlopened by \"" + get_executable_path() +  "\" is not accessible"
1227             " for the namespace \"private_isolated1\"", dlerror());
1228 
1229   extinfo.library_namespace = ns_isolated2;
1230 
1231   // this should work because isolation_path for private_isolated2 includes get_testlib_root()
1232   handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1233   ASSERT_TRUE(handle2 != nullptr) << dlerror();
1234   dlclose(handle2);
1235 
1236   // Check dlopen by absolute path
1237   handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
1238   ASSERT_TRUE(handle2 != nullptr) << dlerror();
1239   dlclose(handle2);
1240 
1241   typedef const char* (*fn_t)();
1242   fn_t ns_get_local_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
1243   ASSERT_TRUE(ns_get_local_string != nullptr) << dlerror();
1244 
1245   ASSERT_STREQ("This string is local to root library", ns_get_local_string());
1246 
1247   fn_t ns_get_private_extern_string =
1248           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
1249   ASSERT_TRUE(ns_get_private_extern_string != nullptr) << dlerror();
1250 
1251   ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string());
1252 
1253   fn_t ns_get_public_extern_string =
1254           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
1255   ASSERT_TRUE(ns_get_public_extern_string != nullptr) << dlerror();
1256 
1257   ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string());
1258 
1259   fn_t ns_get_dlopened_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
1260   ASSERT_TRUE(ns_get_dlopened_string != nullptr) << dlerror();
1261 
1262   ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string());
1263 
1264   dlclose(handle1);
1265 }
1266 
TEST(dlext,ns_shared)1267 TEST(dlext, ns_shared) {
1268   static const char* root_lib = "libnstest_root_not_isolated.so";
1269   static const char* root_lib_isolated = "libnstest_root.so";
1270 
1271   std::string shared_libs = g_core_shared_libs + ":" + g_public_lib;
1272 
1273   // create a parent namespace to use instead of the default namespace. This is
1274   // to make this test be independent from the configuration of the default
1275   // namespace.
1276   android_namespace_t* ns_parent =
1277           android_create_namespace("parent",
1278                                    nullptr,
1279                                    nullptr,
1280                                    ANDROID_NAMESPACE_TYPE_REGULAR,
1281                                    nullptr,
1282                                    nullptr);
1283   ASSERT_TRUE(ns_parent != nullptr) << dlerror();
1284   ASSERT_TRUE(android_link_namespaces(ns_parent, nullptr, g_core_shared_libs.c_str())) << dlerror();
1285 
1286   android_dlextinfo extinfo;
1287   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1288   extinfo.library_namespace = ns_parent;
1289 
1290   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs/" + g_public_lib;
1291   void* handle_public = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
1292   ASSERT_TRUE(handle_public != nullptr) << dlerror();
1293 
1294   android_set_application_target_sdk_version(42U); // something > 23
1295 
1296   ASSERT_TRUE(android_init_anonymous_namespace(shared_libs.c_str(), nullptr)) << dlerror();
1297 
1298   // preload this library to the parent namespace to check if it
1299   // is shared later on.
1300   void* handle_dlopened =
1301           android_dlopen_ext((get_testlib_root() + "/private_namespace_libs/libnstest_dlopened.so").c_str(), RTLD_NOW, &extinfo);
1302   ASSERT_TRUE(handle_dlopened != nullptr) << dlerror();
1303 
1304   // create two child namespaces of 'ns_parent'. One with regular, the other
1305   // with isolated & shared.
1306   android_namespace_t* ns_not_isolated =
1307           android_create_namespace("private",
1308                                    nullptr,
1309                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1310                                    ANDROID_NAMESPACE_TYPE_REGULAR,
1311                                    nullptr,
1312                                    ns_parent);
1313   ASSERT_TRUE(ns_not_isolated != nullptr) << dlerror();
1314   ASSERT_TRUE(android_link_namespaces(ns_not_isolated, ns_parent, g_public_lib)) << dlerror();
1315   ASSERT_TRUE(android_link_namespaces(ns_not_isolated, nullptr, g_core_shared_libs.c_str())) << dlerror();
1316 
1317   android_namespace_t* ns_isolated_shared =
1318           android_create_namespace("private_isolated_shared",
1319                                    nullptr,
1320                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1321                                    ANDROID_NAMESPACE_TYPE_ISOLATED | ANDROID_NAMESPACE_TYPE_SHARED,
1322                                    nullptr,
1323                                    ns_parent);
1324   ASSERT_TRUE(ns_isolated_shared != nullptr) << dlerror();
1325   ASSERT_TRUE(android_link_namespaces(ns_isolated_shared, ns_parent, g_public_lib)) << dlerror();
1326   ASSERT_TRUE(android_link_namespaces(ns_isolated_shared, nullptr, g_core_shared_libs.c_str())) << dlerror();
1327 
1328   ASSERT_TRUE(android_dlopen_ext(root_lib, RTLD_NOW, &extinfo) == nullptr);
1329   ASSERT_STREQ("dlopen failed: library \"libnstest_root_not_isolated.so\" not found", dlerror());
1330 
1331   std::string lib_private_external_path =
1332       get_testlib_root() + "/private_namespace_libs_external/libnstest_private_external.so";
1333 
1334   // Load lib_private_external_path to the parent namespace
1335   // (it should remain invisible for the isolated namespaces after this)
1336   void* handle = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
1337   ASSERT_TRUE(handle != nullptr) << dlerror();
1338 
1339   extinfo.library_namespace = ns_not_isolated;
1340 
1341   void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1342   ASSERT_TRUE(handle1 != nullptr) << dlerror();
1343 
1344   extinfo.library_namespace = ns_isolated_shared;
1345 
1346   void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1347   ASSERT_TRUE(handle2 == nullptr);
1348   ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());
1349 
1350   // Check dlopen by absolute path
1351   handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
1352   ASSERT_TRUE(handle2 == nullptr);
1353   ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" needed"
1354             " or dlopened by \"" + get_executable_path() + "\" is not accessible"
1355             " for the namespace \"private_isolated_shared\"", dlerror());
1356 
1357   // load libnstest_root.so to shared namespace in order to check that everything is different
1358   // except shared libnstest_dlopened.so
1359 
1360   handle2 = android_dlopen_ext(root_lib_isolated, RTLD_NOW, &extinfo);
1361 
1362   typedef const char* (*fn_t)();
1363   fn_t ns_get_local_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
1364   ASSERT_TRUE(ns_get_local_string != nullptr) << dlerror();
1365   fn_t ns_get_local_string_shared = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_local_string"));
1366   ASSERT_TRUE(ns_get_local_string_shared != nullptr) << dlerror();
1367 
1368   ASSERT_STREQ("This string is local to root library", ns_get_local_string());
1369   ASSERT_STREQ("This string is local to root library", ns_get_local_string_shared());
1370   ASSERT_TRUE(ns_get_local_string() != ns_get_local_string_shared());
1371 
1372   fn_t ns_get_private_extern_string =
1373           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
1374   ASSERT_TRUE(ns_get_private_extern_string != nullptr) << dlerror();
1375   fn_t ns_get_private_extern_string_shared =
1376           reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_private_extern_string"));
1377   ASSERT_TRUE(ns_get_private_extern_string_shared() != nullptr) << dlerror();
1378 
1379   ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string());
1380   ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string_shared());
1381   ASSERT_TRUE(ns_get_private_extern_string() != ns_get_private_extern_string_shared());
1382 
1383   fn_t ns_get_public_extern_string =
1384           reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
1385   ASSERT_TRUE(ns_get_public_extern_string != nullptr) << dlerror();
1386   fn_t ns_get_public_extern_string_shared =
1387           reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_public_extern_string"));
1388   ASSERT_TRUE(ns_get_public_extern_string_shared != nullptr) << dlerror();
1389 
1390   ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string());
1391   ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string_shared());
1392   ASSERT_TRUE(ns_get_public_extern_string() == ns_get_public_extern_string_shared());
1393 
1394   fn_t ns_get_dlopened_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
1395   ASSERT_TRUE(ns_get_dlopened_string != nullptr) << dlerror();
1396   fn_t ns_get_dlopened_string_shared = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_dlopened_string"));
1397   ASSERT_TRUE(ns_get_dlopened_string_shared != nullptr) << dlerror();
1398   const char** ns_dlopened_string = static_cast<const char**>(dlsym(handle_dlopened, "g_private_dlopened_string"));
1399   ASSERT_TRUE(ns_dlopened_string != nullptr) << dlerror();
1400 
1401   ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string());
1402   ASSERT_STREQ("This string is from private namespace (dlopened library)", *ns_dlopened_string);
1403   ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string_shared());
1404   ASSERT_TRUE(ns_get_dlopened_string() != ns_get_dlopened_string_shared());
1405   ASSERT_TRUE(*ns_dlopened_string == ns_get_dlopened_string_shared());
1406 
1407   dlclose(handle1);
1408   dlclose(handle2);
1409 }
1410 
TEST(dlext,ns_shared_links_and_paths)1411 TEST(dlext, ns_shared_links_and_paths) {
1412   // Create parent namespace (isolated, not shared)
1413   android_namespace_t* ns_isolated =
1414           android_create_namespace("private_isolated",
1415                                    nullptr,
1416                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1417                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1418                                    (get_testlib_root() + "/public_namespace_libs").c_str(),
1419                                    nullptr);
1420   ASSERT_TRUE(ns_isolated != nullptr) << dlerror();
1421   ASSERT_TRUE(android_link_namespaces(ns_isolated, nullptr, g_core_shared_libs.c_str())) << dlerror();
1422 
1423   // Create shared namespace with ns_isolated parent
1424   android_namespace_t* ns_shared =
1425           android_create_namespace("private_shared",
1426                                    nullptr,
1427                                    nullptr,
1428                                    ANDROID_NAMESPACE_TYPE_SHARED | ANDROID_NAMESPACE_TYPE_ISOLATED,
1429                                    nullptr,
1430                                    ns_isolated);
1431   ASSERT_TRUE(ns_shared != nullptr) << dlerror();
1432 
1433   // 1. Load a library in ns_shared to check that it has inherited
1434   // search path and the link to the default namespace.
1435   android_dlextinfo extinfo;
1436   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1437   extinfo.library_namespace = ns_shared;
1438 
1439   {
1440     void* handle = android_dlopen_ext("libnstest_private.so", RTLD_NOW, &extinfo);
1441     ASSERT_TRUE(handle != nullptr) << dlerror();
1442     const char** ns_private_extern_string = static_cast<const char**>(dlsym(handle, "g_private_extern_string"));
1443     ASSERT_TRUE(ns_private_extern_string != nullptr) << dlerror();
1444     ASSERT_STREQ("This string is from private namespace", *ns_private_extern_string);
1445 
1446     dlclose(handle);
1447   }
1448   // 2. Load another test library by absolute path to check that
1449   // it has inherited permitted_when_isolated_path
1450   {
1451     void* handle = android_dlopen_ext(
1452             (get_testlib_root() + "/public_namespace_libs/libnstest_public.so").c_str(),
1453             RTLD_NOW,
1454             &extinfo);
1455 
1456     ASSERT_TRUE(handle != nullptr) << dlerror();
1457     const char** ns_public_extern_string = static_cast<const char**>(dlsym(handle, "g_public_extern_string"));
1458     ASSERT_TRUE(ns_public_extern_string != nullptr) << dlerror();
1459     ASSERT_STREQ("This string is from public namespace", *ns_public_extern_string);
1460 
1461     dlclose(handle);
1462   }
1463 
1464   // 3. Check that it is still isolated.
1465   {
1466     void* handle = android_dlopen_ext(
1467             (get_testlib_root() + "/libtest_empty.so").c_str(),
1468             RTLD_NOW,
1469             &extinfo);
1470 
1471     ASSERT_TRUE(handle == nullptr);
1472   }
1473 }
1474 
TEST(dlext,ns_shared_dlclose)1475 TEST(dlext, ns_shared_dlclose) {
1476   android_set_application_target_sdk_version(42U); // something > 23
1477 
1478   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr)) << dlerror();
1479 
1480   // preload this library to the default namespace to check if it
1481   // is shared later on.
1482   void* handle_dlopened =
1483           dlopen((get_testlib_root() + "/private_namespace_libs/libnstest_dlopened.so").c_str(), RTLD_NOW);
1484   ASSERT_TRUE(handle_dlopened != nullptr) << dlerror();
1485 
1486   android_namespace_t* ns_isolated_shared =
1487           android_create_namespace("private_isolated_shared",
1488                                    nullptr,
1489                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1490                                    ANDROID_NAMESPACE_TYPE_ISOLATED | ANDROID_NAMESPACE_TYPE_SHARED,
1491                                    nullptr,
1492                                    nullptr);
1493   ASSERT_TRUE(ns_isolated_shared != nullptr) << dlerror();
1494   ASSERT_TRUE(android_link_namespaces(ns_isolated_shared, nullptr, g_core_shared_libs.c_str())) << dlerror();
1495 
1496   // Check if "libnstest_dlopened.so" is loaded (and the same)
1497   android_dlextinfo extinfo;
1498   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1499   extinfo.library_namespace = ns_isolated_shared;
1500 
1501   void* handle = android_dlopen_ext("libnstest_dlopened.so", RTLD_NOW | RTLD_NOLOAD, &extinfo);
1502   ASSERT_TRUE(handle != nullptr) << dlerror();
1503   ASSERT_TRUE(handle == handle_dlopened);
1504   dlclose(handle);
1505   dlclose(handle_dlopened);
1506 
1507   // And now check that the library cannot be found by soname (and is no longer loaded)
1508   handle = android_dlopen_ext("libnstest_dlopened.so", RTLD_NOW | RTLD_NOLOAD, &extinfo);
1509   ASSERT_TRUE(handle == nullptr)
1510       << "Error: libnstest_dlopened.so is still accessible in shared namespace";
1511 
1512   handle = android_dlopen_ext((get_testlib_root() + "/private_namespace_libs/libnstest_dlopened.so").c_str(),
1513                               RTLD_NOW | RTLD_NOLOAD, &extinfo);
1514   ASSERT_TRUE(handle == nullptr)
1515       << "Error: libnstest_dlopened.so is still accessible in shared namespace";
1516 
1517   handle = dlopen("libnstest_dlopened.so", RTLD_NOW | RTLD_NOLOAD);
1518   ASSERT_TRUE(handle == nullptr)
1519       << "Error: libnstest_dlopened.so is still accessible in default namespace";
1520 
1521   handle = dlopen((get_testlib_root() + "/private_namespace_libs/libnstest_dlopened.so").c_str(),
1522                   RTLD_NOW | RTLD_NOLOAD);
1523   ASSERT_TRUE(handle == nullptr)
1524       << "Error: libnstest_dlopened.so is still accessible in default namespace";
1525 
1526   // Now lets see if the soinfo area gets reused in the wrong way:
1527   // load a library to default namespace.
1528   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs/" + g_public_lib;
1529   void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
1530   ASSERT_TRUE(handle_public != nullptr) << dlerror();
1531 
1532   // try to find it in shared namespace
1533   handle = android_dlopen_ext(g_public_lib, RTLD_NOW | RTLD_NOLOAD, &extinfo);
1534   ASSERT_TRUE(handle == nullptr)
1535       << "Error: " << g_public_lib << " is accessible in shared namespace";
1536 }
1537 
TEST(dlext,ns_isolated_rtld_global)1538 TEST(dlext, ns_isolated_rtld_global) {
1539   static const char* root_lib = "libnstest_root.so";
1540   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
1541 
1542   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs";
1543 
1544   android_namespace_t* ns1 =
1545           android_create_namespace("isolated1",
1546                                    nullptr,
1547                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1548                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1549                                    lib_public_path.c_str(),
1550                                    nullptr);
1551   ASSERT_TRUE(ns1 != nullptr) << dlerror();
1552   ASSERT_TRUE(android_link_namespaces(ns1, nullptr, g_core_shared_libs.c_str())) << dlerror();
1553 
1554   android_namespace_t* ns2 =
1555           android_create_namespace("isolated2",
1556                                    nullptr,
1557                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1558                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1559                                    lib_public_path.c_str(),
1560                                    nullptr);
1561   ASSERT_TRUE(ns2 != nullptr) << dlerror();
1562   ASSERT_TRUE(android_link_namespaces(ns2, nullptr, g_core_shared_libs.c_str())) << dlerror();
1563 
1564   android_dlextinfo extinfo;
1565   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1566   extinfo.library_namespace = ns1;
1567 
1568   void* handle_global = android_dlopen_ext((lib_public_path + "/" + g_public_lib).c_str(),
1569                                            RTLD_GLOBAL,
1570                                            &extinfo);
1571 
1572   ASSERT_TRUE(handle_global != nullptr) << dlerror();
1573 
1574   android_namespace_t* ns1_child =
1575           android_create_namespace("isolated1_child",
1576                                    nullptr,
1577                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1578                                    ANDROID_NAMESPACE_TYPE_ISOLATED,
1579                                    nullptr,
1580                                    ns1);
1581 
1582   ASSERT_TRUE(ns1_child != nullptr) << dlerror();
1583   ASSERT_TRUE(android_link_namespaces(ns1_child, nullptr, g_core_shared_libs.c_str())) << dlerror();
1584 
1585   // Now - only ns1 and ns1 child should be able to dlopen root_lib
1586   // attempt to use ns2 should result in dlerror()
1587 
1588   // Check ns1_child first.
1589   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1590   extinfo.library_namespace = ns1_child;
1591 
1592   void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1593   ASSERT_TRUE(handle1 != nullptr) << dlerror();
1594 
1595   // now ns1
1596   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1597   extinfo.library_namespace = ns1;
1598 
1599   handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1600   ASSERT_TRUE(handle1 != nullptr) << dlerror();
1601 
1602   // and ns2 should fail
1603   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1604   extinfo.library_namespace = ns2;
1605 
1606   handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
1607   ASSERT_TRUE(handle1 == nullptr);
1608   ASSERT_STREQ("dlopen failed: library \"libnstest_public.so\" not found", dlerror());
1609 }
1610 
TEST(dlext,ns_anonymous)1611 TEST(dlext, ns_anonymous) {
1612   static const char* root_lib = "libnstest_root.so";
1613   std::string shared_libs = g_core_shared_libs + ":" + g_public_lib;
1614 
1615   const std::string lib_public_path = get_testlib_root() + "/public_namespace_libs/" + g_public_lib;
1616   void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
1617 
1618   ASSERT_TRUE(handle_public != nullptr) << dlerror();
1619 
1620   ASSERT_TRUE(
1621           android_init_anonymous_namespace(shared_libs.c_str(),
1622                                            (get_testlib_root() + "/private_namespace_libs").c_str())
1623       ) << dlerror();
1624 
1625   android_namespace_t* ns =
1626           android_create_namespace("private",
1627                                    nullptr,
1628                                    (get_testlib_root() + "/private_namespace_libs").c_str(),
1629                                    ANDROID_NAMESPACE_TYPE_REGULAR,
1630                                    nullptr,
1631                                    nullptr);
1632 
1633   ASSERT_TRUE(ns != nullptr) << dlerror();
1634   ASSERT_TRUE(android_link_namespaces(ns, nullptr, shared_libs.c_str())) << dlerror();
1635 
1636   std::string private_library_absolute_path = get_testlib_root() + "/private_namespace_libs/" + root_lib;
1637 
1638   android_dlextinfo extinfo;
1639   extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
1640   extinfo.library_namespace = ns;
1641 
1642   // we are going to copy this library to anonymous mmap and call the copy of ns_get_dlopened_string
1643   void* handle = android_dlopen_ext(private_library_absolute_path.c_str(), RTLD_NOW, &extinfo);
1644   ASSERT_TRUE(handle != nullptr) << dlerror();
1645 
1646   uintptr_t ns_get_dlopened_string_addr =
1647       reinterpret_cast<uintptr_t>(dlsym(handle, "ns_get_dlopened_string"));
1648   ASSERT_TRUE(ns_get_dlopened_string_addr != 0) << dlerror();
1649   typedef const char* (*fn_t)();
1650   fn_t ns_get_dlopened_string_private = reinterpret_cast<fn_t>(ns_get_dlopened_string_addr);
1651 
1652   std::vector<map_record> maps;
1653   Maps::parse_maps(&maps);
1654 
1655   uintptr_t addr_start = 0;
1656   uintptr_t addr_end = 0;
1657   std::vector<map_record> maps_to_copy;
1658 
1659   for (const auto& rec : maps) {
1660     if (rec.pathname == private_library_absolute_path) {
1661       if (addr_start == 0) {
1662         addr_start = rec.addr_start;
1663       }
1664       addr_end = rec.addr_end;
1665 
1666       maps_to_copy.push_back(rec);
1667     }
1668   }
1669 
1670   // some sanity checks..
1671   ASSERT_TRUE(addr_start > 0);
1672   ASSERT_TRUE(addr_end > 0);
1673   ASSERT_EQ(3U, maps_to_copy.size());
1674   ASSERT_TRUE(ns_get_dlopened_string_addr > addr_start);
1675   ASSERT_TRUE(ns_get_dlopened_string_addr < addr_end);
1676 
1677   // copy
1678   uintptr_t reserved_addr = reinterpret_cast<uintptr_t>(mmap(nullptr, addr_end - addr_start,
1679                                                              PROT_NONE, MAP_ANON | MAP_PRIVATE,
1680                                                              -1, 0));
1681   ASSERT_TRUE(reinterpret_cast<void*>(reserved_addr) != MAP_FAILED);
1682 
1683   for (const auto& rec : maps_to_copy) {
1684     uintptr_t offset = rec.addr_start - addr_start;
1685     size_t size = rec.addr_end - rec.addr_start;
1686     void* addr = reinterpret_cast<void*>(reserved_addr + offset);
1687     void* map = mmap(addr, size, PROT_READ | PROT_WRITE,
1688                      MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
1689     ASSERT_TRUE(map != MAP_FAILED);
1690     memcpy(map, reinterpret_cast<void*>(rec.addr_start), size);
1691     mprotect(map, size, rec.perms);
1692   }
1693 
1694   // call the function copy
1695   uintptr_t ns_get_dlopened_string_offset  = ns_get_dlopened_string_addr - addr_start;
1696   fn_t ns_get_dlopened_string_anon = reinterpret_cast<fn_t>(reserved_addr + ns_get_dlopened_string_offset);
1697   ASSERT_STREQ("This string is from private namespace (dlopened library)",
1698                ns_get_dlopened_string_anon());
1699 
1700   // They should belong to different namespaces (private and anonymous)
1701   ASSERT_STREQ("This string is from private namespace (dlopened library)",
1702                ns_get_dlopened_string_private());
1703 
1704   ASSERT_TRUE(ns_get_dlopened_string_anon() != ns_get_dlopened_string_private());
1705 }
1706 
TEST(dlext,dlopen_handle_value_platform)1707 TEST(dlext, dlopen_handle_value_platform) {
1708   void* handle = dlopen("libtest_dlsym_from_this.so", RTLD_NOW | RTLD_LOCAL);
1709   ASSERT_TRUE((reinterpret_cast<uintptr_t>(handle) & 1) != 0)
1710           << "dlopen should return odd value for the handle";
1711   dlclose(handle);
1712 }
1713 
TEST(dlext,dlopen_handle_value_app_compat)1714 TEST(dlext, dlopen_handle_value_app_compat) {
1715   android_set_application_target_sdk_version(__ANDROID_API_M__);
1716   void* handle = dlopen("libtest_dlsym_from_this.so", RTLD_NOW | RTLD_LOCAL);
1717   ASSERT_TRUE(reinterpret_cast<uintptr_t>(handle) % sizeof(uintptr_t) == 0)
1718           << "dlopen should return valid pointer";
1719   dlclose(handle);
1720 }
1721