Introducing linker namespaces
Bug: http://b/22548808
Change-Id: Ia3af3c0a167f1d16447a3d83bb045d143319b1e1
diff --git a/linker/linker.cpp b/linker/linker.cpp
index 31ed1ec..32e3063 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -70,11 +70,55 @@
#undef ELF_ST_TYPE
#define ELF_ST_TYPE(x) (static_cast<uint32_t>(x) & 0xf)
+struct android_namespace_t {
+ public:
+ android_namespace_t() : name_(nullptr), is_isolated_(false) {}
+
+ const char* get_name() const { return name_; }
+ void set_name(const char* name) { name_ = name; }
+
+ bool is_isolated() const { return is_isolated_; }
+ void set_isolated(bool isolated) { is_isolated_ = isolated; }
+
+ const std::vector<std::string>& get_ld_library_paths() const {
+ return ld_library_paths_;
+ }
+ void set_ld_library_paths(std::vector<std::string>&& library_paths) {
+ ld_library_paths_ = library_paths;
+ }
+
+ const std::vector<std::string>& get_default_library_paths() const {
+ return default_library_paths_;
+ }
+ void set_default_library_paths(std::vector<std::string>&& library_paths) {
+ default_library_paths_ = library_paths;
+ }
+
+ soinfo::soinfo_list_t& soinfo_list() { return soinfo_list_; }
+
+ // For isolated namespaces - checks if the file is on the search path;
+ // always returns true for not isolated namespace.
+ bool is_accessible(const std::string& path);
+
+ private:
+ const char* name_;
+ bool is_isolated_;
+ std::vector<std::string> ld_library_paths_;
+ std::vector<std::string> default_library_paths_;
+ soinfo::soinfo_list_t soinfo_list_;
+
+ DISALLOW_COPY_AND_ASSIGN(android_namespace_t);
+};
+
+android_namespace_t g_default_namespace;
+
static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf);
static LinkerTypeAllocator<soinfo> g_soinfo_allocator;
static LinkerTypeAllocator<LinkedListEntry<soinfo>> g_soinfo_links_allocator;
+static LinkerTypeAllocator<android_namespace_t> g_namespace_allocator;
+
static soinfo* solist;
static soinfo* sonext;
static soinfo* somain; // main process, always the one after libdl_info
@@ -107,14 +151,15 @@
static const ElfW(Versym) kVersymNotNeeded = 0;
static const ElfW(Versym) kVersymGlobal = 1;
-static const char* const kZipFileSeparator = "!/";
static const char* const* g_default_ld_paths;
-static std::vector<std::string> g_ld_library_paths;
static std::vector<std::string> g_ld_preload_names;
static std::vector<soinfo*> g_ld_preloads;
+static bool g_public_namespace_initialized;
+static soinfo::soinfo_list_t g_public_namespace;
+
__LIBC_HIDDEN__ int g_ld_debug_verbosity;
__LIBC_HIDDEN__ abort_msg_t* g_abort_message = nullptr; // For debuggerd.
@@ -247,6 +292,26 @@
rtld_db_dlactivity();
}
+bool android_namespace_t::is_accessible(const std::string& file) {
+ if (!is_isolated_) {
+ return true;
+ }
+
+ for (const auto& dir : ld_library_paths_) {
+ if (file_is_in_dir(file, dir)) {
+ return true;
+ }
+ }
+
+ for (const auto& dir : default_library_paths_) {
+ if (file_is_in_dir(file, dir)) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
LinkedListEntry<soinfo>* SoinfoListAllocator::alloc() {
return g_soinfo_links_allocator.alloc();
}
@@ -255,18 +320,22 @@
g_soinfo_links_allocator.free(entry);
}
-static soinfo* soinfo_alloc(const char* name, struct stat* file_stat,
- off64_t file_offset, uint32_t rtld_flags) {
+static soinfo* soinfo_alloc(android_namespace_t* ns, const char* name,
+ struct stat* file_stat, off64_t file_offset,
+ uint32_t rtld_flags) {
if (strlen(name) >= PATH_MAX) {
DL_ERR("library name \"%s\" too long", name);
return nullptr;
}
- soinfo* si = new (g_soinfo_allocator.alloc()) soinfo(name, file_stat, file_offset, rtld_flags);
+ soinfo* si = new (g_soinfo_allocator.alloc()) soinfo(ns, name, file_stat,
+ file_offset, rtld_flags);
sonext->next = si;
sonext = si;
+ ns->soinfo_list().push_back(si);
+
TRACE("name %s: allocated soinfo @ %p", name, si);
return si;
}
@@ -307,33 +376,130 @@
sonext = prev;
}
+ // remove from the namespace
+ si->get_namespace()->soinfo_list().remove_if([&](soinfo* candidate) {
+ return si == candidate;
+ });
+
si->~soinfo();
g_soinfo_allocator.free(si);
}
-static void parse_path(const char* path, const char* delimiters,
+// For every path element this function checks of it exists, and is a directory,
+// and normalizes it:
+// 1. For regular path it converts it to realpath()
+// 2. For path in a zip file it uses realpath on the zipfile
+// normalizes entry name by calling normalize_path function.
+static void resolve_paths(std::vector<std::string>& paths,
+ std::vector<std::string>* resolved_paths) {
+ resolved_paths->clear();
+ for (const auto& path : paths) {
+ char resolved_path[PATH_MAX];
+ const char* original_path = path.c_str();
+ if (realpath(original_path, resolved_path) != nullptr) {
+ struct stat s;
+ if (stat(resolved_path, &s) == 0) {
+ if (S_ISDIR(s.st_mode)) {
+ resolved_paths->push_back(resolved_path);
+ } else {
+ DL_WARN("Warning: \"%s\" is not a directory (excluding from path)", resolved_path);
+ continue;
+ }
+ } else {
+ DL_WARN("Warning: cannot stat file \"%s\": %s", resolved_path, strerror(errno));
+ continue;
+ }
+ } else {
+ std::string zip_path;
+ std::string entry_path;
+
+ std::string normalized_path;
+
+ if (!normalize_path(original_path, &normalized_path)) {
+ DL_WARN("Warning: unable to normalize \"%s\"", original_path);
+ continue;
+ }
+
+ if (parse_zip_path(normalized_path.c_str(), &zip_path, &entry_path)) {
+ if (realpath(zip_path.c_str(), resolved_path) == nullptr) {
+ DL_WARN("Warning: unable to resolve \"%s\": %s", zip_path.c_str(), strerror(errno));
+ continue;
+ }
+
+ ZipArchiveHandle handle = nullptr;
+ if (OpenArchive(resolved_path, &handle) != 0) {
+ DL_WARN("Warning: unable to open zip archive: %s", resolved_path);
+ continue;
+ }
+
+ // Check if zip-file has a dir with entry_path name
+ void* cookie = nullptr;
+ std::string prefix_str = entry_path + "/";
+ ZipString prefix(prefix_str.c_str());
+
+ ZipEntry out_data;
+ ZipString out_name;
+
+ int32_t error_code;
+
+ if ((error_code = StartIteration(handle, &cookie, &prefix, nullptr)) != 0) {
+ DL_WARN("Unable to iterate over zip-archive entries \"%s\";"
+ " error code: %d", zip_path.c_str(), error_code);
+ continue;
+ }
+
+ if (Next(cookie, &out_data, &out_name) != 0) {
+ DL_WARN("Unable to find entries starting with \"%s\" in \"%s\"",
+ prefix_str.c_str(), zip_path.c_str());
+ continue;
+ }
+
+ auto zip_guard = make_scope_guard([&]() {
+ if (cookie != nullptr) {
+ EndIteration(cookie);
+ }
+ CloseArchive(handle);
+ });
+
+ resolved_paths->push_back(std::string(resolved_path) + kZipFileSeparator + entry_path);
+ }
+ }
+ }
+}
+
+static void split_path(const char* path, const char* delimiters,
std::vector<std::string>* paths) {
- paths->clear();
if (path != nullptr) {
*paths = android::base::Split(path, delimiters);
}
}
+static void parse_path(const char* path, const char* delimiters,
+ std::vector<std::string>* resolved_paths) {
+ std::vector<std::string> paths;
+ split_path(path, delimiters, &paths);
+ resolve_paths(paths, resolved_paths);
+}
+
static void parse_LD_LIBRARY_PATH(const char* path) {
- parse_path(path, ":", &g_ld_library_paths);
+ std::vector<std::string> ld_libary_paths;
+ parse_path(path, ":", &ld_libary_paths);
+ g_default_namespace.set_ld_library_paths(std::move(ld_libary_paths));
}
void soinfo::set_dt_runpath(const char* path) {
- if (!has_min_version(2)) {
+ if (!has_min_version(3)) {
return;
}
- parse_path(path, ":", &dt_runpath_);
+ std::vector<std::string> runpaths;
+
+ split_path(path, ":", &runpaths);
std::string origin = dirname(get_realpath());
// FIXME: add $LIB and $PLATFORM.
std::pair<std::string, std::string> substs[] = {{"ORIGIN", origin}};
- for (auto&& s : dt_runpath_) {
+ for (auto&& s : runpaths) {
size_t pos = 0;
while (pos < s.size()) {
pos = s.find("$", pos);
@@ -356,11 +522,16 @@
++pos;
}
}
+
+ resolve_paths(runpaths, &dt_runpath_);
}
static void parse_LD_PRELOAD(const char* path) {
- // We have historically supported ':' as well as ' ' in LD_PRELOAD.
- parse_path(path, " :", &g_ld_preload_names);
+ g_ld_preload_names.clear();
+ if (path != nullptr) {
+ // We have historically supported ':' as well as ' ' in LD_PRELOAD.
+ g_ld_preload_names = android::base::Split(path, " :");
+ }
}
static bool realpath_fd(int fd, std::string* realpath) {
@@ -688,8 +859,9 @@
return true;
}
-soinfo::soinfo(const char* realpath, const struct stat* file_stat,
- off64_t file_offset, int rtld_flags) {
+soinfo::soinfo(android_namespace_t* ns, const char* realpath,
+ const struct stat* file_stat, off64_t file_offset,
+ int rtld_flags) {
memset(this, 0, sizeof(*this));
if (realpath != nullptr) {
@@ -706,6 +878,7 @@
}
this->rtld_flags_ = rtld_flags;
+ this->namespace_ = ns;
}
@@ -857,6 +1030,7 @@
void protect_data(int protection) {
g_soinfo_allocator.protect_all(protection);
g_soinfo_links_allocator.protect_all(protection);
+ g_namespace_allocator.protect_all(protection);
}
static size_t ref_count_;
@@ -1096,7 +1270,7 @@
// libraries and they are loaded in breath-first (correct) order we can just execute
// dlsym(RTLD_DEFAULT, ...); instead of doing two stage lookup.
if (si == somain) {
- return dlsym_linear_lookup(name, found, nullptr, RTLD_DEFAULT);
+ return dlsym_linear_lookup(&g_default_namespace, name, found, nullptr, RTLD_DEFAULT);
}
SymbolName symbol_name(name);
@@ -1108,24 +1282,29 @@
beginning of the global solist. Otherwise the search starts at the
specified soinfo (for RTLD_NEXT).
*/
-const ElfW(Sym)* dlsym_linear_lookup(const char* name,
+const ElfW(Sym)* dlsym_linear_lookup(android_namespace_t* ns,
+ const char* name,
soinfo** found,
soinfo* caller,
void* handle) {
SymbolName symbol_name(name);
- soinfo* start = solist;
+ soinfo::soinfo_list_t& soinfo_list = ns->soinfo_list();
+ soinfo::soinfo_list_t::iterator start = soinfo_list.begin();
if (handle == RTLD_NEXT) {
if (caller == nullptr) {
return nullptr;
} else {
- start = caller->next;
+ soinfo::soinfo_list_t::iterator it = soinfo_list.find(caller);
+ CHECK (it != soinfo_list.end());
+ start = ++it;
}
}
const ElfW(Sym)* s = nullptr;
- for (soinfo* si = start; si != nullptr; si = si->next) {
+ for (soinfo::soinfo_list_t::iterator it = start, end = soinfo_list.end(); it != end; ++it) {
+ soinfo* si = *it;
// Do not skip RTLD_LOCAL libraries in dlsym(RTLD_DEFAULT, ...)
// if the library is opened by application with target api level <= 22
// See http://b/21565766
@@ -1337,35 +1516,13 @@
return true;
}
-static int open_library_on_default_path(const char* name, off64_t* file_offset, std::string* realpath) {
- for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
- char buf[512];
- if (!format_path(buf, sizeof(buf), g_default_ld_paths[i], name)) {
- continue;
- }
-
- int fd = TEMP_FAILURE_RETRY(open(buf, O_RDONLY | O_CLOEXEC));
- if (fd != -1) {
- *file_offset = 0;
- if (!realpath_fd(fd, realpath)) {
- PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", buf);
- *realpath = buf;
- }
- return fd;
- }
- }
-
- return -1;
-}
-
static int open_library_on_paths(ZipArchiveCache* zip_archive_cache,
const char* name, off64_t* file_offset,
const std::vector<std::string>& paths,
std::string* realpath) {
- for (const auto& path_str : paths) {
+ for (const auto& path : paths) {
char buf[512];
- const char* const path = path_str.c_str();
- if (!format_path(buf, sizeof(buf), path, name)) {
+ if (!format_path(buf, sizeof(buf), path.c_str(), name)) {
continue;
}
@@ -1393,39 +1550,49 @@
return -1;
}
-static int open_library(ZipArchiveCache* zip_archive_cache,
+static int open_library(android_namespace_t* ns,
+ ZipArchiveCache* zip_archive_cache,
const char* name, soinfo *needed_by,
off64_t* file_offset, std::string* realpath) {
TRACE("[ opening %s ]", name);
// If the name contains a slash, we should attempt to open it directly and not search the paths.
if (strchr(name, '/') != nullptr) {
+ int fd = -1;
+
if (strstr(name, kZipFileSeparator) != nullptr) {
- int fd = open_library_in_zipfile(zip_archive_cache, name, file_offset, realpath);
+ fd = open_library_in_zipfile(zip_archive_cache, name, file_offset, realpath);
+ }
+
+ if (fd == -1) {
+ fd = TEMP_FAILURE_RETRY(open(name, O_RDONLY | O_CLOEXEC));
if (fd != -1) {
- return fd;
+ *file_offset = 0;
+ if (!realpath_fd(fd, realpath)) {
+ PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", name);
+ *realpath = name;
+ }
}
}
- int fd = TEMP_FAILURE_RETRY(open(name, O_RDONLY | O_CLOEXEC));
- if (fd != -1) {
- *file_offset = 0;
- if (!realpath_fd(fd, realpath)) {
- PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", name);
- *realpath = name;
- }
+ if (fd != -1 && !ns->is_accessible(*realpath)) {
+ fd = -1;
}
return fd;
}
- // Otherwise we try LD_LIBRARY_PATH first, and fall back to the built-in well known paths.
- int fd = open_library_on_paths(zip_archive_cache, name, file_offset, g_ld_library_paths, realpath);
+ // Otherwise we try LD_LIBRARY_PATH first, and fall back to the default library path
+ int fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_ld_library_paths(), realpath);
if (fd == -1 && needed_by != nullptr) {
fd = open_library_on_paths(zip_archive_cache, name, file_offset, needed_by->get_dt_runpath(), realpath);
+ // Check if the library is accessible
+ if (fd != -1 && !ns->is_accessible(*realpath)) {
+ fd = -1;
+ }
}
if (fd == -1) {
- fd = open_library_on_default_path(name, file_offset, realpath);
+ fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_default_library_paths(), realpath);
}
return fd;
@@ -1464,7 +1631,8 @@
}
}
-static bool load_library(LoadTask* task,
+static bool load_library(android_namespace_t* ns,
+ LoadTask* task,
LoadTaskList* load_tasks,
int rtld_flags,
const std::string& realpath) {
@@ -1495,18 +1663,30 @@
// Check for symlink and other situations where
// file can have different names, unless ANDROID_DLEXT_FORCE_LOAD is set
if (extinfo == nullptr || (extinfo->flags & ANDROID_DLEXT_FORCE_LOAD) == 0) {
- for (soinfo* si = solist; si != nullptr; si = si->next) {
- if (si->get_st_dev() != 0 &&
- si->get_st_ino() != 0 &&
- si->get_st_dev() == file_stat.st_dev &&
- si->get_st_ino() == file_stat.st_ino &&
- si->get_file_offset() == file_offset) {
- TRACE("library \"%s\" is already loaded under different name/path \"%s\" - "
- "will return existing soinfo", name, si->get_realpath());
- task->set_soinfo(si);
- return true;
+ auto predicate = [&](soinfo* si) {
+ return si->get_st_dev() != 0 &&
+ si->get_st_ino() != 0 &&
+ si->get_st_dev() == file_stat.st_dev &&
+ si->get_st_ino() == file_stat.st_ino &&
+ si->get_file_offset() == file_offset;
+ };
+
+ soinfo* si = ns->soinfo_list().find_if(predicate);
+
+ // check public namespace
+ if (si == nullptr) {
+ si = g_public_namespace.find_if(predicate);
+ if (si != nullptr) {
+ ns->soinfo_list().push_back(si);
}
}
+
+ if (si != nullptr) {
+ TRACE("library \"%s\" is already loaded under different name/path \"%s\" - "
+ "will return existing soinfo", name, si->get_realpath());
+ task->set_soinfo(si);
+ return true;
+ }
}
if ((rtld_flags & RTLD_NOLOAD) != 0) {
@@ -1514,7 +1694,7 @@
return false;
}
- soinfo* si = soinfo_alloc(realpath.c_str(), &file_stat, file_offset, rtld_flags);
+ soinfo* si = soinfo_alloc(ns, realpath.c_str(), &file_stat, file_offset, rtld_flags);
if (si == nullptr) {
return false;
}
@@ -1550,7 +1730,8 @@
}
-static bool load_library(LoadTask* task,
+static bool load_library(android_namespace_t* ns,
+ LoadTask* task,
ZipArchiveCache* zip_archive_cache,
LoadTaskList* load_tasks,
int rtld_flags) {
@@ -1574,11 +1755,11 @@
task->set_fd(extinfo->library_fd, false);
task->set_file_offset(file_offset);
- return load_library(task, load_tasks, rtld_flags, realpath);
+ return load_library(ns, task, load_tasks, rtld_flags, realpath);
}
// Open the file.
- int fd = open_library(zip_archive_cache, name, needed_by, &file_offset, &realpath);
+ int fd = open_library(ns, zip_archive_cache, name, needed_by, &file_offset, &realpath);
if (fd == -1) {
DL_ERR("library \"%s\" not found", name);
return false;
@@ -1587,14 +1768,15 @@
task->set_fd(fd, true);
task->set_file_offset(file_offset);
- return load_library(task, load_tasks, rtld_flags, realpath);
+ return load_library(ns, task, load_tasks, rtld_flags, realpath);
}
// Returns true if library was found and false in 2 cases
-// 1. The library was found but loaded under different target_sdk_version
-// (*candidate != nullptr)
+// 1. (for default namespace only) The library was found but loaded under different
+// target_sdk_version (*candidate != nullptr)
// 2. The library was not found by soname (*candidate is nullptr)
-static bool find_loaded_library_by_soname(const char* name, soinfo** candidate) {
+static bool find_loaded_library_by_soname(android_namespace_t* ns,
+ const char* name, soinfo** candidate) {
*candidate = nullptr;
// Ignore filename with path.
@@ -1604,7 +1786,7 @@
uint32_t target_sdk_version = get_application_target_sdk_version();
- for (soinfo* si = solist; si != nullptr; si = si->next) {
+ return !ns->soinfo_list().visit([&](soinfo* si) {
const char* soname = si->get_soname();
if (soname != nullptr && (strcmp(name, soname) == 0)) {
// If the library was opened under different target sdk version
@@ -1614,36 +1796,52 @@
// in any case.
bool is_libdl = si == solist;
if (is_libdl || (si->get_dt_flags_1() & DF_1_GLOBAL) != 0 ||
- !si->is_linked() || si->get_target_sdk_version() == target_sdk_version) {
+ !si->is_linked() || si->get_target_sdk_version() == target_sdk_version ||
+ ns != &g_default_namespace) {
*candidate = si;
- return true;
+ return false;
} else if (*candidate == nullptr) {
- // for the different sdk version - remember the first library.
+ // for the different sdk version in the default namespace
+ // remember the first library.
*candidate = si;
}
}
- }
- return false;
+ return true;
+ });
}
-static bool find_library_internal(LoadTask* task,
+static bool find_library_internal(android_namespace_t* ns,
+ LoadTask* task,
ZipArchiveCache* zip_archive_cache,
LoadTaskList* load_tasks,
int rtld_flags) {
soinfo* candidate;
- if (find_loaded_library_by_soname(task->get_name(), &candidate)) {
+ if (find_loaded_library_by_soname(ns, task->get_name(), &candidate)) {
task->set_soinfo(candidate);
return true;
}
+ if (ns != &g_default_namespace) {
+ // check public namespace
+ candidate = g_public_namespace.find_if([&](soinfo* si) {
+ return strcmp(task->get_name(), si->get_soname()) == 0;
+ });
+
+ if (candidate != nullptr) {
+ ns->soinfo_list().push_back(candidate);
+ task->set_soinfo(candidate);
+ return true;
+ }
+ }
+
// Library might still be loaded, the accurate detection
// of this fact is done by load_library.
TRACE("[ '%s' find_loaded_library_by_soname returned false (*candidate=%s@%p). Trying harder...]",
task->get_name(), candidate == nullptr ? "n/a" : candidate->get_realpath(), candidate);
- if (load_library(task, zip_archive_cache, load_tasks, rtld_flags)) {
+ if (load_library(ns, task, zip_archive_cache, load_tasks, rtld_flags)) {
return true;
} else {
// In case we were unable to load the library but there
@@ -1667,13 +1865,13 @@
//
// This group consists of the main executable, LD_PRELOADs
// and libraries with the DF_1_GLOBAL flag set.
-static soinfo::soinfo_list_t make_global_group() {
+static soinfo::soinfo_list_t make_global_group(android_namespace_t* ns) {
soinfo::soinfo_list_t global_group;
- for (soinfo* si = somain; si != nullptr; si = si->next) {
+ ns->soinfo_list().for_each([&](soinfo* si) {
if ((si->get_dt_flags_1() & DF_1_GLOBAL) != 0) {
global_group.push_back(si);
}
- }
+ });
return global_group;
}
@@ -1690,7 +1888,8 @@
// not their transitive dependencies) as children of the start_with library.
// This is false when find_libraries is called for dlopen(), when newly loaded
// libraries must form a disjoint tree.
-static bool find_libraries(soinfo* start_with,
+static bool find_libraries(android_namespace_t* ns,
+ soinfo* start_with,
const char* const library_names[],
size_t library_names_count, soinfo* soinfos[],
std::vector<soinfo*>* ld_preloads,
@@ -1707,7 +1906,7 @@
}
// Construct global_group.
- soinfo::soinfo_list_t global_group = make_global_group();
+ soinfo::soinfo_list_t global_group = make_global_group(ns);
// If soinfos array is null allocate one on stack.
// The array is needed in case of failure; for example
@@ -1749,7 +1948,7 @@
bool is_dt_needed = needed_by != nullptr && (needed_by != start_with || add_as_children);
task->set_extinfo(is_dt_needed ? nullptr : extinfo);
- if(!find_library_internal(task, &zip_archive_cache, &load_tasks, rtld_flags)) {
+ if(!find_library_internal(ns, task, &zip_archive_cache, &load_tasks, rtld_flags)) {
return false;
}
@@ -1850,14 +2049,15 @@
return linked;
}
-static soinfo* find_library(const char* name, int rtld_flags,
+static soinfo* find_library(android_namespace_t* ns,
+ const char* name, int rtld_flags,
const android_dlextinfo* extinfo,
soinfo* needed_by) {
soinfo* si;
if (name == nullptr) {
si = somain;
- } else if (!find_libraries(needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
+ } else if (!find_libraries(ns, needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
extinfo, /* add_as_children */ false)) {
return nullptr;
}
@@ -1920,7 +2120,9 @@
TRACE("deprecated (old format of soinfo): %s needs to unload %s",
si->get_realpath(), library_name);
- soinfo* needed = find_library(library_name, RTLD_NOLOAD, nullptr, nullptr);
+ soinfo* needed = find_library(si->get_namespace(),
+ library_name, RTLD_NOLOAD, nullptr, nullptr);
+
if (needed != nullptr) {
// Not found: for example if symlink was deleted between dlopen and dlclose
// Since we cannot really handle errors at this point - print and continue.
@@ -1992,6 +2194,9 @@
DL_ERR("invalid flags to dlopen: %x", flags);
return nullptr;
}
+
+ android_namespace_t* ns = caller->get_namespace();
+
if (extinfo != nullptr) {
if ((extinfo->flags & ~(ANDROID_DLEXT_VALID_FLAG_BITS)) != 0) {
DL_ERR("invalid extended flags to android_dlopen_ext: 0x%" PRIx64, extinfo->flags);
@@ -2011,13 +2216,22 @@
"compatible with ANDROID_DLEXT_RESERVED_ADDRESS/ANDROID_DLEXT_RESERVED_ADDRESS_HINT");
return nullptr;
}
+
+ if ((extinfo->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0) {
+ if (extinfo->library_namespace == nullptr) {
+ DL_ERR("ANDROID_DLEXT_USE_NAMESPACE is set but extinfo->library_namespace is null");
+ return nullptr;
+ }
+ ns = extinfo->library_namespace;
+ }
}
ProtectedDataGuard guard;
- soinfo* si = find_library(name, flags, extinfo, caller);
+ soinfo* si = find_library(ns, name, flags, extinfo, caller);
if (si != nullptr) {
si->call_constructors();
}
+
return si;
}
@@ -2026,6 +2240,67 @@
soinfo_unload(si);
}
+bool init_public_namespace(const char* libs) {
+ CHECK(libs != nullptr);
+ if (g_public_namespace_initialized) {
+ DL_ERR("Public namespace has already been initialized.");
+ return false;
+ }
+
+ std::vector<std::string> sonames = android::base::Split(libs, ":");
+
+ ProtectedDataGuard guard;
+
+ auto failure_guard = make_scope_guard([&]() {
+ g_public_namespace.clear();
+ });
+
+ soinfo* candidate;
+ for (const auto& soname : sonames) {
+ if (!find_loaded_library_by_soname(&g_default_namespace, soname.c_str(), &candidate)) {
+ DL_ERR("Error initializing public namespace: \"%s\" was not found"
+ " in the default namespace", soname.c_str());
+ return false;
+ }
+
+ candidate->set_nodelete();
+ g_public_namespace.push_back(candidate);
+ }
+
+ failure_guard.disable();
+ g_public_namespace_initialized = true;
+ return true;
+}
+
+android_namespace_t* create_namespace(const char* name,
+ const char* ld_library_path,
+ const char* default_library_path,
+ bool is_isolated) {
+ if (!g_public_namespace_initialized) {
+ DL_ERR("Cannot create namespace: public namespace is not initialized.");
+ return nullptr;
+ }
+
+ ProtectedDataGuard guard;
+ std::vector<std::string> ld_library_paths;
+ std::vector<std::string> default_library_paths;
+
+ parse_path(ld_library_path, ":", &ld_library_paths);
+ parse_path(default_library_path, ":", &default_library_paths);
+
+ android_namespace_t* ns = new (g_namespace_allocator.alloc()) android_namespace_t();
+ ns->set_name(name);
+ ns->set_isolated(is_isolated);
+ ns->set_ld_library_paths(std::move(ld_library_paths));
+ ns->set_default_library_paths(std::move(default_library_paths));
+
+ // TODO(dimtiry): Should this be global group of caller's namespace?
+ auto global_group = make_global_group(&g_default_namespace);
+ std::copy(global_group.begin(), global_group.end(), std::back_inserter(ns->soinfo_list()));
+
+ return ns;
+}
+
static ElfW(Addr) call_ifunc_resolver(ElfW(Addr) resolver_addr) {
typedef ElfW(Addr) (*ifunc_resolver_t)(void);
ifunc_resolver_t ifunc_resolver = reinterpret_cast<ifunc_resolver_t>(resolver_addr);
@@ -2694,6 +2969,10 @@
}
}
+void soinfo::set_nodelete() {
+ rtld_flags_ |= RTLD_NODELETE;
+}
+
const char* soinfo::get_realpath() const {
#if defined(__work_around_b_24465209__)
if (has_min_version(2)) {
@@ -2760,13 +3039,21 @@
static std::vector<std::string> g_empty_runpath;
const std::vector<std::string>& soinfo::get_dt_runpath() const {
- if (has_min_version(2)) {
+ if (has_min_version(3)) {
return dt_runpath_;
}
return g_empty_runpath;
}
+android_namespace_t* soinfo::get_namespace() {
+ if (has_min_version(3)) {
+ return namespace_;
+ }
+
+ return &g_default_namespace;
+}
+
ElfW(Addr) soinfo::resolve_symbol_address(const ElfW(Sym)* s) const {
if (ELF_ST_TYPE(s->st_info) == STT_GNU_IFUNC) {
return call_ifunc_resolver(s->st_value + load_bias);
@@ -3464,7 +3751,8 @@
* be on the soinfo list.
*/
static void init_linker_info_for_gdb(ElfW(Addr) linker_base) {
- linker_soinfo_for_gdb = new (linker_soinfo_for_gdb_buf) soinfo(LINKER_PATH, nullptr, 0, 0);
+ linker_soinfo_for_gdb = new (linker_soinfo_for_gdb_buf) soinfo(nullptr, LINKER_PATH,
+ nullptr, 0, 0);
linker_soinfo_for_gdb->load_bias = linker_base;
@@ -3481,14 +3769,25 @@
insert_soinfo_into_debug_map(linker_soinfo_for_gdb);
}
-static void init_default_ld_library_path() {
+static void init_default_namespace() {
+ g_default_namespace.set_name("(default)");
+ g_default_namespace.set_isolated(false);
+
const char *interp = phdr_table_get_interpreter_name(somain->phdr, somain->phnum,
somain->load_bias);
const char* bname = basename(interp);
- if (bname && (strcmp(bname, "linker_asan") == 0 || strcmp(bname, "linker_asan64") == 0))
+ if (bname && (strcmp(bname, "linker_asan") == 0 || strcmp(bname, "linker_asan64") == 0)) {
g_default_ld_paths = kAsanDefaultLdPaths;
- else
+ } else {
g_default_ld_paths = kDefaultLdPaths;
+ }
+
+ std::vector<std::string> ld_default_paths;
+ for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
+ ld_default_paths.push_back(g_default_ld_paths[i]);
+ }
+
+ g_default_namespace.set_default_library_paths(std::move(ld_default_paths));
};
extern "C" int __system_properties_init(void);
@@ -3529,7 +3828,7 @@
INFO("[ android linker & debugger ]");
- soinfo* si = soinfo_alloc(args.argv[0], nullptr, 0, RTLD_GLOBAL);
+ soinfo* si = soinfo_alloc(&g_default_namespace, args.argv[0], nullptr, 0, RTLD_GLOBAL);
if (si == nullptr) {
exit(EXIT_FAILURE);
}
@@ -3581,11 +3880,10 @@
somain = si;
- init_default_ld_library_path();
+ init_default_namespace();
if (!si->prelink_image()) {
- __libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
- exit(EXIT_FAILURE);
+ __libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
// add somain to global group
@@ -3613,15 +3911,13 @@
needed_library_name_list.copy_to_array(needed_library_names, needed_libraries_count);
if (needed_libraries_count > 0 &&
- !find_libraries(si, needed_library_names, needed_libraries_count, nullptr,
- &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
+ !find_libraries(&g_default_namespace, si, needed_library_names, needed_libraries_count,
+ nullptr, &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
/* add_as_children */ true)) {
- __libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
- exit(EXIT_FAILURE);
+ __libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
} else if (needed_libraries_count == 0) {
if (!si->link_image(g_empty_list, soinfo::soinfo_list_t::make_list(si), nullptr)) {
- __libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
- exit(EXIT_FAILURE);
+ __libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
si->increment_ref_count();
}
@@ -3730,7 +4026,7 @@
ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(linker_addr);
ElfW(Phdr)* phdr = reinterpret_cast<ElfW(Phdr)*>(linker_addr + elf_hdr->e_phoff);
- soinfo linker_so(nullptr, nullptr, 0, 0);
+ soinfo linker_so(nullptr, nullptr, nullptr, 0, 0);
// If the linker is not acting as PT_INTERP entry_point is equal to
// _start. Which means that the linker is running as an executable and
@@ -3739,7 +4035,7 @@
// This happens when user tries to run 'adb shell /system/bin/linker'
// see also https://code.google.com/p/android/issues/detail?id=63174
if (reinterpret_cast<ElfW(Addr)>(&_start) == entry_point) {
- __libc_fatal("This is %s, the helper program for shared library executables.\n", args.argv[0]);
+ __libc_fatal("This is %s, the helper program for shared library executables.", args.argv[0]);
}
linker_so.base = linker_addr;
@@ -3757,15 +4053,7 @@
// are not yet initialized, and therefore we cannot use linked_list.push_*
// functions at this point.
if (!(linker_so.prelink_image() && linker_so.link_image(g_empty_list, g_empty_list, nullptr))) {
- // It would be nice to print an error message, but if the linker
- // can't link itself, there's no guarantee that we'll be able to
- // call write() (because it involves a GOT reference). We may as
- // well try though...
- const char* msg = "CANNOT LINK EXECUTABLE: ";
- write(2, msg, strlen(msg));
- write(2, __linker_dl_err_buf, strlen(__linker_dl_err_buf));
- write(2, "\n", 1);
- _exit(EXIT_FAILURE);
+ __libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
__libc_init_main_thread(args);
@@ -3781,6 +4069,7 @@
// before get_libdl_info().
solist = get_libdl_info();
sonext = get_libdl_info();
+ g_default_namespace.soinfo_list().push_back(get_libdl_info());
// We have successfully fixed our own relocations. It's safe to run
// the main part of the linker now.