Merge "Test that /dev/stdin, /dev/stdout, and /dev/stderr are all present."
diff --git a/libc/include/android/api-level.h b/libc/include/android/api-level.h
index 7a909d7..6ed6c0a 100644
--- a/libc/include/android/api-level.h
+++ b/libc/include/android/api-level.h
@@ -59,5 +59,6 @@
#define __ANDROID_API_O__ 26
#define __ANDROID_API_O_MR1__ 27
#define __ANDROID_API_P__ 28
+#define __ANDROID_API_Q__ 29
#endif
diff --git a/linker/dlfcn.cpp b/linker/dlfcn.cpp
index 4b84537..dfe8e8c 100644
--- a/linker/dlfcn.cpp
+++ b/linker/dlfcn.cpp
@@ -303,9 +303,7 @@
static soinfo* __libdl_info = nullptr;
// This is used by the dynamic linker. Every process gets these symbols for free.
-soinfo* get_libdl_info(const char* linker_path,
- const soinfo& linker_si,
- const link_map& linker_map) {
+soinfo* get_libdl_info(const char* linker_path, const soinfo& linker_si) {
CHECK((linker_si.flags_ & FLAG_GNU_HASH) != 0);
if (__libdl_info == nullptr) {
@@ -314,6 +312,8 @@
__libdl_info->strtab_ = linker_si.strtab_;
__libdl_info->symtab_ = linker_si.symtab_;
__libdl_info->load_bias = linker_si.load_bias;
+ __libdl_info->phdr = linker_si.phdr;
+ __libdl_info->phnum = linker_si.phnum;
__libdl_info->gnu_nbucket_ = linker_si.gnu_nbucket_;
__libdl_info->gnu_maskwords_ = linker_si.gnu_maskwords_;
@@ -328,9 +328,6 @@
__libdl_info->soname_ = linker_si.soname_;
__libdl_info->target_sdk_version_ = __ANDROID_API__;
__libdl_info->generate_handle();
- __libdl_info->link_map_head.l_addr = linker_map.l_addr;
- __libdl_info->link_map_head.l_name = linker_map.l_name;
- __libdl_info->link_map_head.l_ld = linker_map.l_ld;
#if defined(__work_around_b_24465209__)
strlcpy(__libdl_info->old_name_, __libdl_info->soname_, sizeof(__libdl_info->old_name_));
#endif
diff --git a/linker/linker.h b/linker/linker.h
index 260c89d..7aa7e5f 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -99,9 +99,7 @@
void count_relocation(RelocationKind kind);
-soinfo* get_libdl_info(const char* linker_path,
- const soinfo& linker_si,
- const link_map& linker_map);
+soinfo* get_libdl_info(const char* linker_path, const soinfo& linker_si);
soinfo* find_containing_library(const void* p);
diff --git a/linker/linker_main.cpp b/linker/linker_main.cpp
index af47619..c5e0b96 100644
--- a/linker/linker_main.cpp
+++ b/linker/linker_main.cpp
@@ -67,6 +67,7 @@
static soinfo* solist;
static soinfo* sonext;
static soinfo* somain; // main process, always the one after libdl_info
+static soinfo* solinker;
static soinfo* vdso; // vdso if present
void solist_add_soinfo(soinfo* si) {
@@ -170,29 +171,13 @@
vdso = si;
}
-/* gdb expects the linker to be in the debug shared object list.
- * Without this, gdb has trouble locating the linker's ".text"
- * and ".plt" sections. Gdb could also potentially use this to
- * relocate the offset of our exported 'rtld_db_dlactivity' symbol.
- * Note that the linker shouldn't be on the soinfo list.
- */
-static link_map linker_link_map;
-
-static void init_linker_info_for_gdb(ElfW(Addr) linker_base, char* linker_path) {
- linker_link_map.l_addr = linker_base;
- linker_link_map.l_name = linker_path;
-
- /*
- * Set the dynamic field in the link map otherwise gdb will complain with
- * the following:
- * warning: .dynamic section for "/system/bin/linker" is not at the
- * expected address (wrong library or version mismatch?)
- */
- ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(linker_base);
- ElfW(Phdr)* phdr = reinterpret_cast<ElfW(Phdr)*>(linker_base + elf_hdr->e_phoff);
- phdr_table_get_dynamic_section(phdr, elf_hdr->e_phnum, linker_base,
- &linker_link_map.l_ld, nullptr);
-
+// Initializes an soinfo's link_map_head field using other fields from the
+// soinfo (phdr, phnum, load_bias).
+static void init_link_map_head(soinfo& info, const char* linker_path) {
+ auto& map = info.link_map_head;
+ map.l_addr = info.load_bias;
+ map.l_name = const_cast<char*>(linker_path);
+ phdr_table_get_dynamic_section(info.phdr, info.phnum, info.load_bias, &map.l_ld, nullptr);
}
extern "C" int __system_properties_init(void);
@@ -303,32 +288,32 @@
stat("/init", &file_stat);
}
+ // Initialize the main exe's soinfo.
const char* executable_path = get_executable_path();
soinfo* si = soinfo_alloc(&g_default_namespace, executable_path, &file_stat, 0, RTLD_GLOBAL);
-
- // Bootstrap the link map, the main exe always needs to be first.
+ somain = si;
+ si->phdr = reinterpret_cast<ElfW(Phdr)*>(args.getauxval(AT_PHDR));
+ si->phnum = args.getauxval(AT_PHNUM);
+ get_elf_base_from_phdr(si->phdr, si->phnum, &si->base, &si->load_bias);
+ si->size = phdr_table_get_load_size(si->phdr, si->phnum);
+ si->dynamic = nullptr;
si->set_main_executable();
- link_map* map = &(si->link_map_head);
+ init_link_map_head(*si, executable_path);
// Register the main executable and the linker upfront to have
// gdb aware of them before loading the rest of the dependency
// tree.
- map->l_addr = 0;
- map->l_name = const_cast<char*>(executable_path);
- insert_link_map_into_debug_map(map);
- insert_link_map_into_debug_map(&linker_link_map);
+ //
+ // gdb expects the linker to be in the debug shared object list.
+ // Without this, gdb has trouble locating the linker's ".text"
+ // and ".plt" sections. Gdb could also potentially use this to
+ // relocate the offset of our exported 'rtld_db_dlactivity' symbol.
+ //
+ insert_link_map_into_debug_map(&si->link_map_head);
+ insert_link_map_into_debug_map(&solinker->link_map_head);
add_vdso(args);
- // Extract information passed from the kernel.
- si->phdr = reinterpret_cast<ElfW(Phdr)*>(args.getauxval(AT_PHDR));
- si->phnum = args.getauxval(AT_PHNUM);
-
- get_elf_base_from_phdr(si->phdr, si->phnum, &si->base, &si->load_bias);
- si->size = phdr_table_get_load_size(si->phdr, si->phnum);
-
- si->dynamic = nullptr;
-
ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(si->base);
// We haven't supported non-PIE since Lollipop for security reasons.
@@ -351,8 +336,6 @@
parse_LD_LIBRARY_PATH(ldpath_env);
parse_LD_PRELOAD(ldpreload_env);
- somain = si;
-
std::vector<android_namespace_t*> namespaces = init_default_namespaces(executable_path);
if (!si->prelink_image()) __linker_cannot_link(g_argv[0]);
@@ -411,13 +394,6 @@
__get_tls()[TLS_SLOT_BIONIC_PREINIT] = &args;
si->call_pre_init_constructors();
-
- /* After the prelink_image, the si->load_bias is initialized.
- * For so lib, the map->l_addr will be updated in notify_gdb_of_load.
- * We need to update this value for so exe here. So Unwind_Backtrace
- * for some arch like x86 could work correctly within so exe.
- */
- map->l_addr = si->load_bias;
si->call_constructors();
#if TIMING
@@ -508,9 +484,7 @@
}
static ElfW(Addr) __attribute__((noinline))
-__linker_init_post_relocation(KernelArgumentBlock& args,
- ElfW(Addr) linker_addr,
- soinfo& linker_so);
+__linker_init_post_relocation(KernelArgumentBlock& args, soinfo& linker_so);
/*
* This is the entry point for the linker, called from begin.S. This
@@ -543,18 +517,18 @@
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, nullptr, 0, 0);
+ soinfo tmp_linker_so(nullptr, nullptr, nullptr, 0, 0);
- linker_so.base = linker_addr;
- linker_so.size = phdr_table_get_load_size(phdr, elf_hdr->e_phnum);
- linker_so.load_bias = get_elf_exec_load_bias(elf_hdr);
- linker_so.dynamic = nullptr;
- linker_so.phdr = phdr;
- linker_so.phnum = elf_hdr->e_phnum;
- linker_so.set_linker_flag();
+ tmp_linker_so.base = linker_addr;
+ tmp_linker_so.size = phdr_table_get_load_size(phdr, elf_hdr->e_phnum);
+ tmp_linker_so.load_bias = get_elf_exec_load_bias(elf_hdr);
+ tmp_linker_so.dynamic = nullptr;
+ tmp_linker_so.phdr = phdr;
+ tmp_linker_so.phnum = elf_hdr->e_phnum;
+ tmp_linker_so.set_linker_flag();
// Prelink the linker so we can access linker globals.
- if (!linker_so.prelink_image()) __linker_cannot_link(args.argv[0]);
+ if (!tmp_linker_so.prelink_image()) __linker_cannot_link(args.argv[0]);
// This might not be obvious... The reasons why we pass g_empty_list
// in place of local_group here are (1) we do not really need it, because
@@ -562,9 +536,9 @@
// itself without having to look into local_group and (2) allocators
// are not yet initialized, and therefore we cannot use linked_list.push_*
// functions at this point.
- if (!linker_so.link_image(g_empty_list, g_empty_list, nullptr)) __linker_cannot_link(args.argv[0]);
+ if (!tmp_linker_so.link_image(g_empty_list, g_empty_list, nullptr)) __linker_cannot_link(args.argv[0]);
- return __linker_init_post_relocation(args, linker_addr, linker_so);
+ return __linker_init_post_relocation(args, tmp_linker_so);
}
/*
@@ -574,15 +548,13 @@
* function, so avoid inlining this function (http://b/80503879).
*/
static ElfW(Addr) __attribute__((noinline))
-__linker_init_post_relocation(KernelArgumentBlock& args,
- ElfW(Addr) linker_addr,
- soinfo& linker_so) {
+__linker_init_post_relocation(KernelArgumentBlock& args, soinfo& tmp_linker_so) {
// Initialize the main thread (including TLS, so system calls really work).
__libc_init_main_thread(args);
// We didn't protect the linker's RELRO pages in link_image because we
// couldn't make system calls on x86 at that point, but we can now...
- if (!linker_so.protect_relro()) __linker_cannot_link(args.argv[0]);
+ if (!tmp_linker_so.protect_relro()) __linker_cannot_link(args.argv[0]);
// Initialize the linker/libc.so shared global inside the linker.
static libc_shared_globals shared_globals;
@@ -599,7 +571,7 @@
g_envp = args.envp;
// Initialize the linker's own global variables
- linker_so.call_constructors();
+ tmp_linker_so.call_constructors();
// 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
@@ -615,13 +587,12 @@
exit(0);
}
- init_linker_info_for_gdb(linker_addr, kLinkerPath);
-
// Initialize static variables. Note that in order to
// get correct libdl_info we need to call constructors
// before get_libdl_info().
- sonext = solist = get_libdl_info(kLinkerPath, linker_so, linker_link_map);
- g_default_namespace.add_soinfo(solist);
+ sonext = solist = solinker = get_libdl_info(kLinkerPath, tmp_linker_so);
+ g_default_namespace.add_soinfo(solinker);
+ init_link_map_head(*solinker, kLinkerPath);
args.abort_message_ptr = &g_abort_message;
ElfW(Addr) start_address = linker_main(args);
diff --git a/linker/linker_soinfo.h b/linker/linker_soinfo.h
index 09e5065..7331b2f 100644
--- a/linker/linker_soinfo.h
+++ b/linker/linker_soinfo.h
@@ -361,9 +361,7 @@
android_namespace_list_t secondary_namespaces_;
uintptr_t handle_;
- friend soinfo* get_libdl_info(const char* linker_path,
- const soinfo& linker_si,
- const link_map& linker_map);
+ friend soinfo* get_libdl_info(const char* linker_path, const soinfo& linker_si);
// version >= 4
ElfW(Relr)* relr_;
diff --git a/tests/link_test.cpp b/tests/link_test.cpp
index a5430a9..1bdee9f 100644
--- a/tests/link_test.cpp
+++ b/tests/link_test.cpp
@@ -29,6 +29,12 @@
#include <gtest/gtest.h>
#include <link.h>
+#if __has_include(<sys/auxv.h>)
+#include <sys/auxv.h>
+#endif
+
+#include <string>
+#include <unordered_map>
TEST(link, dl_iterate_phdr_early_exit) {
static size_t call_count = 0;
@@ -40,7 +46,7 @@
TEST(link, dl_iterate_phdr) {
struct Functor {
static int Callback(dl_phdr_info* i, size_t s, void* data) {
- reinterpret_cast<Functor*>(data)->DoChecks(i, s);
+ static_cast<Functor*>(data)->DoChecks(i, s);
return 0;
}
void DoChecks(dl_phdr_info* info, size_t s) {
@@ -48,7 +54,12 @@
ASSERT_TRUE(info->dlpi_name != nullptr);
+ // An ELF file must have at least a PT_LOAD program header.
+ ASSERT_NE(nullptr, info->dlpi_phdr);
+ ASSERT_NE(0, info->dlpi_phnum);
+
// Find the first PT_LOAD program header so we can find the ELF header.
+ bool found_load = false;
for (ElfW(Half) i = 0; i < info->dlpi_phnum; ++i) {
const ElfW(Phdr)* phdr = reinterpret_cast<const ElfW(Phdr)*>(&info->dlpi_phdr[i]);
if (phdr->p_type == PT_LOAD) {
@@ -58,15 +69,124 @@
ASSERT_EQ(0, memcmp(ehdr, ELFMAG, SELFMAG));
// Does the e_phnum match what dl_iterate_phdr told us?
ASSERT_EQ(info->dlpi_phnum, ehdr->e_phnum);
+ found_load = true;
break;
}
}
+ ASSERT_EQ(true, found_load);
}
size_t count;
} f = {};
ASSERT_EQ(0, dl_iterate_phdr(Functor::Callback, &f));
}
+struct ProgHdr {
+ const ElfW(Phdr)* table;
+ size_t size;
+};
+
+__attribute__((__unused__))
+static ElfW(Addr) find_exe_load_bias(const ProgHdr& phdr) {
+ for (size_t i = 0; i < phdr.size; ++i) {
+ if (phdr.table[i].p_type == PT_PHDR) {
+ return reinterpret_cast<ElfW(Addr)>(phdr.table) - phdr.table[i].p_vaddr;
+ }
+ }
+ return 0;
+}
+
+__attribute__((__unused__))
+static ElfW(Dyn)* find_dynamic(const ProgHdr& phdr, ElfW(Addr) load_bias) {
+ for (size_t i = 0; i < phdr.size; ++i) {
+ if (phdr.table[i].p_type == PT_DYNAMIC) {
+ return reinterpret_cast<ElfW(Dyn)*>(phdr.table[i].p_vaddr + load_bias);
+ }
+ }
+ return nullptr;
+}
+
+__attribute__((__unused__))
+static r_debug* find_exe_r_debug(ElfW(Dyn)* dynamic) {
+ for (ElfW(Dyn)* d = dynamic; d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_DEBUG) {
+ return reinterpret_cast<r_debug*>(d->d_un.d_val);
+ }
+ }
+ return nullptr;
+}
+
+// Walk the DT_DEBUG/_r_debug global module list and compare it with the same
+// information from dl_iterate_phdr. Verify that the executable appears first
+// in _r_debug.
+TEST(link, r_debug) {
+#if __has_include(<sys/auxv.h>)
+ // Find the executable's PT_DYNAMIC segment and DT_DEBUG value. The linker
+ // will write the address of its _r_debug global into the .dynamic section.
+ ProgHdr exe_phdr = {
+ .table = reinterpret_cast<ElfW(Phdr)*>(getauxval(AT_PHDR)),
+ .size = getauxval(AT_PHNUM)
+ };
+ ASSERT_NE(nullptr, exe_phdr.table);
+ ElfW(Addr) exe_load_bias = find_exe_load_bias(exe_phdr);
+ ASSERT_NE(0u, exe_load_bias);
+ ElfW(Dyn)* exe_dynamic = find_dynamic(exe_phdr, exe_load_bias);
+ ASSERT_NE(nullptr, exe_dynamic);
+ r_debug* dbg = find_exe_r_debug(exe_dynamic);
+ ASSERT_NE(nullptr, dbg);
+
+ // Use dl_iterate_phdr to build a table mapping from load bias values to
+ // solib names and PT_DYNAMIC segments.
+ struct DlIterateInfo {
+ std::string name;
+ ElfW(Dyn)* dynamic;
+ };
+ struct Functor {
+ std::unordered_map<ElfW(Addr), DlIterateInfo> dl_iter_mods;
+ static int Callback(dl_phdr_info* i, size_t s, void* data) {
+ static_cast<Functor*>(data)->AddModule(i, s);
+ return 0;
+ }
+ void AddModule(dl_phdr_info* info, size_t s) {
+ ASSERT_EQ(sizeof(dl_phdr_info), s);
+ ASSERT_TRUE(dl_iter_mods.find(info->dlpi_addr) == dl_iter_mods.end());
+ ASSERT_TRUE(info->dlpi_name != nullptr);
+ dl_iter_mods[info->dlpi_addr] = {
+ .name = info->dlpi_name,
+ .dynamic = find_dynamic({ info->dlpi_phdr, info->dlpi_phnum }, info->dlpi_addr)
+ };
+ }
+ } f = {};
+ ASSERT_EQ(0, dl_iterate_phdr(Functor::Callback, &f));
+
+ size_t map_size = 0;
+
+ for (link_map* map = dbg->r_map; map != nullptr; map = map->l_next) {
+ ASSERT_NE(0u, map->l_addr);
+ ASSERT_NE(nullptr, map->l_ld);
+ ASSERT_NE(nullptr, map->l_name);
+
+ auto it = f.dl_iter_mods.find(map->l_addr);
+ ASSERT_TRUE(it != f.dl_iter_mods.end());
+ const DlIterateInfo& info = it->second;
+ ASSERT_EQ(info.name, map->l_name);
+ ASSERT_EQ(info.dynamic, map->l_ld);
+
+ ++map_size;
+ }
+
+ // _r_debug and dl_iterate_phdr should report the same set of modules. We
+ // verified above that every _r_debug module was reported by dl_iterate_phdr,
+ // so checking the sizes verifies the converse.
+ ASSERT_EQ(f.dl_iter_mods.size(), map_size);
+
+ // Make sure the first entry is the executable. gdbserver assumes this and
+ // removes the first entry from its list of shared objects that it sends back
+ // to gdb.
+ ASSERT_EQ(exe_load_bias, dbg->r_map->l_addr);
+ ASSERT_EQ(exe_dynamic, dbg->r_map->l_ld);
+#endif
+}
+
#if __arm__
static uintptr_t read_exidx_func(uintptr_t* entry) {
int32_t offset = *entry;