Merge af1f724947d8a37c13e6e7163ba35481b8ba4dcc on remote branch

Change-Id: Icd977d266c2e4654e328bec1e08ff704d4287b3e

11 files changed, 63 insertions, 55 deletions

diff --git a/apex/Android.bp b/apex/Android.bp
index 90a14b245..4879f474c 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -58,6 +58,7 @@ apex {
         "bionic-linker-config",
     ],
     updatable: false,
+    generate_hashtree: false,
 }
 
 sdk {
diff --git a/libc/arch-arm/bionic/__bionic_clone.S b/libc/arch-arm/bionic/__bionic_clone.S
index 6669b93a2..3fe212b47 100644
--- a/libc/arch-arm/bionic/__bionic_clone.S
+++ b/libc/arch-arm/bionic/__bionic_clone.S
@@ -61,6 +61,8 @@ ENTRY_PRIVATE(__bionic_clone)
     b       __set_errno_internal
 
 .L_bc_child:
+    # We're in the child now. Set the end of the frame record chain.
+    mov    fp, #0
     # Setting lr to 0 will make the unwinder stop at __start_thread.
     mov    lr, #0
     # Call __start_thread with the 'fn' and 'arg' we stored on the child stack.
diff --git a/libc/arch-common/bionic/crtbegin.c b/libc/arch-common/bionic/crtbegin.c
index 628783789..5f681c53c 100644
--- a/libc/arch-common/bionic/crtbegin.c
+++ b/libc/arch-common/bionic/crtbegin.c
@@ -49,13 +49,15 @@ __used static void _start_main(void* raw_args) {
 #define POST "; .size _start, .-_start"
 
 #if defined(__aarch64__)
-__asm__(PRE "bti j; mov x0,sp; b _start_main" POST);
+__asm__(PRE "bti j; mov x29,#0; mov x30,#0; mov x0,sp; b _start_main" POST);
 #elif defined(__arm__)
-__asm__(PRE "mov r0,sp; b _start_main" POST);
+__asm__(PRE "mov fp,#0; mov lr,#0; mov r0,sp; b _start_main" POST);
 #elif defined(__i386__)
-__asm__(PRE "movl %esp,%eax; andl $~0xf,%esp; subl $12,%esp; pushl %eax; calll _start_main" POST);
+__asm__(PRE
+        "xorl %ebp,%ebp; movl %esp,%eax; andl $~0xf,%esp; subl $12,%esp; pushl %eax;"
+        "calll _start_main" POST);
 #elif defined(__x86_64__)
-__asm__(PRE "movq %rsp,%rdi; andq $~0xf,%rsp; callq _start_main" POST);
+__asm__(PRE "xorl %ebp, %ebp; movq %rsp,%rdi; andq $~0xf,%rsp; callq _start_main" POST);
 #else
 #error unsupported architecture
 #endif
diff --git a/libc/arch-x86/bionic/__bionic_clone.S b/libc/arch-x86/bionic/__bionic_clone.S
index b682b4863..f0c58a00d 100644
--- a/libc/arch-x86/bionic/__bionic_clone.S
+++ b/libc/arch-x86/bionic/__bionic_clone.S
@@ -45,6 +45,7 @@ ENTRY_PRIVATE(__bionic_clone)
 .L_bc_child:
         # We don't want anyone to unwind past this point.
         .cfi_undefined %eip
+        .cfi_undefined %ebp
         call    __start_thread
         hlt
 
diff --git a/libc/bionic/malloc_heapprofd.cpp b/libc/bionic/malloc_heapprofd.cpp
index 198bcbab7..741b45e98 100644
--- a/libc/bionic/malloc_heapprofd.cpp
+++ b/libc/bionic/malloc_heapprofd.cpp
@@ -325,12 +325,12 @@ void HeapprofdRememberHookConflict() {
 
 static void CommonInstallHooks(libc_globals* globals) {
   void* impl_handle = atomic_load(&gHeapprofdHandle);
-  bool reusing_handle = impl_handle != nullptr;
-  if (!reusing_handle) {
+  if (impl_handle == nullptr) {
     impl_handle = LoadSharedLibrary(kHeapprofdSharedLib, kHeapprofdPrefix, &globals->malloc_dispatch_table);
     if (impl_handle == nullptr) {
       return;
     }
+    atomic_store(&gHeapprofdHandle, impl_handle);
   } else if (!InitSharedLibrary(impl_handle, kHeapprofdSharedLib, kHeapprofdPrefix, &globals->malloc_dispatch_table)) {
     return;
   }
@@ -341,11 +341,7 @@ static void CommonInstallHooks(libc_globals* globals) {
   // MaybeModifyGlobals locks at this point.
   atomic_store(&gPreviousDefaultDispatchTable, GetDefaultDispatchTable());
 
-  if (FinishInstallHooks(globals, nullptr, kHeapprofdPrefix)) {
-    atomic_store(&gHeapprofdHandle, impl_handle);
-  } else if (!reusing_handle) {
-    dlclose(impl_handle);
-  }
+  FinishInstallHooks(globals, nullptr, kHeapprofdPrefix);
 }
 
 void HeapprofdInstallHooksAtInit(libc_globals* globals) {
diff --git a/libc/bionic/pthread_create.cpp b/libc/bionic/pthread_create.cpp
index 46d9e8672..121b26f82 100644
--- a/libc/bionic/pthread_create.cpp
+++ b/libc/bionic/pthread_create.cpp
@@ -331,6 +331,11 @@ void __set_stack_and_tls_vma_name(bool is_main_thread) {
 extern "C" int __rt_sigprocmask(int, const sigset64_t*, sigset64_t*, size_t);
 
 __attribute__((no_sanitize("hwaddress")))
+#ifdef __aarch64__
+// This function doesn't return, but it does appear in stack traces. Avoid using return PAC in this
+// function because we may end up resetting IA, which may confuse unwinders due to mismatching keys.
+__attribute__((target("branch-protection=bti")))
+#endif
 static int __pthread_start(void* arg) {
   pthread_internal_t* thread = reinterpret_cast<pthread_internal_t*>(arg);
 
diff --git a/libc/dns/resolv/res_cache.c b/libc/dns/resolv/res_cache.c
index c1c2059ef..f4c590f60 100644
--- a/libc/dns/resolv/res_cache.c
+++ b/libc/dns/resolv/res_cache.c
@@ -28,7 +28,6 @@
 
 #include "resolv_cache.h"
 
-#include <ctype.h>
 #include <resolv.h>
 #include <stdarg.h>
 #include <stdio.h>
@@ -454,22 +453,6 @@ typedef struct {
     const uint8_t*  cursor;
 } DnsPacket;
 
-static int
-memcasecmp( const unsigned char *s1, const unsigned char *s2, int len )
-{
-    for ( int i = 0; i < len; i++ )
-    {
-        int ch1 = *s1++;
-        int ch2 = *s2++;
-        int d = tolower(ch1) - tolower(ch2);
-        if (d != 0)
-        {
-            return d;
-        }
-    }
-    return 0;
-}
-
 static void
 _dnsPacket_init( DnsPacket*  packet, const uint8_t*  buff, int  bufflen )
 {
@@ -782,7 +765,6 @@ _dnsPacket_hashBytes( DnsPacket*  packet, int  numBytes, unsigned  hash )
 
     while (numBytes > 0 && p < end) {
         hash = hash*FNV_MULT ^ *p++;
-        numBytes -= 1;
     }
     packet->cursor = p;
     return hash;
@@ -796,12 +778,14 @@ _dnsPacket_hashQName( DnsPacket*  packet, unsigned  hash )
     const uint8_t*  end = packet->end;
 
     for (;;) {
+        int  c;
+
         if (p >= end) {  /* should not happen */
             XLOG("%s: INTERNAL_ERROR: read-overflow !!\n", __FUNCTION__);
             break;
         }
 
-        int c = *p++;
+        c = *p++;
 
         if (c == 0)
             break;
@@ -815,12 +799,9 @@ _dnsPacket_hashQName( DnsPacket*  packet, unsigned  hash )
                     __FUNCTION__);
             break;
         }
-
         while (c > 0) {
-            int ch = *p++;
-            ch = tolower(ch);
-            hash = hash * (FNV_MULT ^ ch);
-            c--;
+            hash = hash*FNV_MULT ^ *p++;
+            c   -= 1;
         }
     }
     packet->cursor = p;
@@ -907,12 +888,14 @@ _dnsPacket_isEqualDomainName( DnsPacket*  pack1, DnsPacket*  pack2 )
     const uint8_t*  end2 = pack2->end;
 
     for (;;) {
+        int  c1, c2;
+
         if (p1 >= end1 || p2 >= end2) {
             XLOG("%s: INTERNAL_ERROR: read-overflow !!\n", __FUNCTION__);
             break;
         }
-        int c1 = *p1++;
-        int c2 = *p2++;
+        c1 = *p1++;
+        c2 = *p2++;
         if (c1 != c2)
             break;
 
@@ -930,7 +913,7 @@ _dnsPacket_isEqualDomainName( DnsPacket*  pack1, DnsPacket*  pack2 )
                     __FUNCTION__);
             break;
         }
-        if (memcasecmp(p1, p2, c1) != 0)
+        if (memcmp(p1, p2, c1) != 0)
             break;
         p1 += c1;
         p2 += c1;
diff --git a/libc/malloc_debug/PointerData.cpp b/libc/malloc_debug/PointerData.cpp
index a15b1b13a..4c5559bb9 100644
--- a/libc/malloc_debug/PointerData.cpp
+++ b/libc/malloc_debug/PointerData.cpp
@@ -591,8 +591,8 @@ void PointerData::DumpLiveToFile(int fd) {
       dprintf(fd, "  bt_info");
       for (const auto& frame : *info.backtrace_info) {
         dprintf(fd, " {");
-        if (frame.map_info != nullptr && !frame.map_info->name.empty()) {
-          dprintf(fd, "\"%s\"", frame.map_info->name.c_str());
+        if (frame.map_info != nullptr && !frame.map_info->name().empty()) {
+          dprintf(fd, "\"%s\"", frame.map_info->name().c_str());
         } else {
           dprintf(fd, "\"\"");
         }
diff --git a/libc/malloc_debug/UnwindBacktrace.cpp b/libc/malloc_debug/UnwindBacktrace.cpp
index 92fb3fa96..128991bd9 100644
--- a/libc/malloc_debug/UnwindBacktrace.cpp
+++ b/libc/malloc_debug/UnwindBacktrace.cpp
@@ -90,14 +90,14 @@ void UnwindLog(const std::vector<unwindstack::LocalFrameData>& frame_info) {
     unwindstack::MapInfo* map_info = info->map_info;
 
     std::string line = android::base::StringPrintf("          #%0zd  pc %" PAD_PTR "  ", i, info->rel_pc);
-    if (map_info->offset != 0) {
-      line += android::base::StringPrintf("(offset 0x%" PRIx64 ") ", map_info->offset);
+    if (map_info->offset() != 0) {
+      line += android::base::StringPrintf("(offset 0x%" PRIx64 ") ", map_info->offset());
     }
 
-    if (map_info->name.empty()) {
-      line += android::base::StringPrintf("<anonymous:%" PRIx64 ">", map_info->start);
+    if (map_info->name().empty()) {
+      line += android::base::StringPrintf("<anonymous:%" PRIx64 ">", map_info->start());
     } else {
-      line += map_info->name;
+      line += map_info->name();
     }
 
     if (!info->function_name.empty()) {
diff --git a/tests/dl_test.cpp b/tests/dl_test.cpp
index 766f27a0b..47bf13374 100644
--- a/tests/dl_test.cpp
+++ b/tests/dl_test.cpp
@@ -264,8 +264,11 @@ static void create_ld_config_file(const char* config_file) {
 #endif
 
 #if defined(__BIONIC__)
-static bool is_debuggable_build() {
-  return android::base::GetBoolProperty("ro.debuggable", false);
+// This test can't rely on ro.debuggable, because it might have been forced on
+// in a user build ("Force Debuggable"). In that configuration, ro.debuggable is
+// true, but Bionic's LD_CONFIG_FILE testing support is still disabled.
+static bool is_user_build() {
+  return android::base::GetProperty("ro.build.type", "user") == std::string("user");
 }
 #endif
 
@@ -282,7 +285,7 @@ static bool is_debuggable_build() {
 TEST(dl, exec_with_ld_config_file) {
 #if defined(__BIONIC__)
   SKIP_WITH_HWASAN << "libclang_rt.hwasan is not found with custom ld config";
-  if (!is_debuggable_build()) {
+  if (is_user_build()) {
     GTEST_SKIP() << "LD_CONFIG_FILE is not supported on user build";
   }
   std::string helper = GetTestlibRoot() +
@@ -319,7 +322,7 @@ TEST(dl, exec_with_ld_config_file) {
 TEST(dl, exec_with_ld_config_file_with_ld_preload) {
 #if defined(__BIONIC__)
   SKIP_WITH_HWASAN << "libclang_rt.hwasan is not found with custom ld config";
-  if (!is_debuggable_build()) {
+  if (is_user_build()) {
     GTEST_SKIP() << "LD_CONFIG_FILE is not supported on user build";
   }
   std::string helper = GetTestlibRoot() +
@@ -356,8 +359,8 @@ TEST(dl, disable_ld_config_file) {
     // This test is only for CTS.
     GTEST_SKIP() << "test is not supported with root uid";
   }
-  if (is_debuggable_build()) {
-    GTEST_SKIP() << "test is not supported on debuggable build";
+  if (!is_user_build()) {
+    GTEST_SKIP() << "test requires user build";
   }
 
   std::string error_message = std::string("CANNOT LINK EXECUTABLE ") +
diff --git a/tests/stack_unwinding_test.cpp b/tests/stack_unwinding_test.cpp
index 0ff6f30a6..2f891a6e1 100644
--- a/tests/stack_unwinding_test.cpp
+++ b/tests/stack_unwinding_test.cpp
@@ -66,13 +66,28 @@ static int noinline unwind_one_frame_deeper() {
   return count;
 }
 
-TEST(stack_unwinding, easy) {
+static void UnwindTest() {
   int count = 0;
   _Unwind_Backtrace(FrameCounter, &count);
   int deeper_count = unwind_one_frame_deeper();
   ASSERT_EQ(count + 1, deeper_count);
 }
 
+TEST(stack_unwinding, easy) {
+  UnwindTest();
+}
+
+TEST(stack_unwinding, thread) {
+  pthread_t thread;
+  ASSERT_EQ(0, pthread_create(&thread, nullptr, [](void*) -> void* {
+    UnwindTest();
+    return nullptr;
+  }, nullptr));
+  void *retval;
+  ASSERT_EQ(0, pthread_join(thread, &retval));
+  EXPECT_EQ(nullptr, retval);
+}
+
 struct UnwindData {
   volatile bool signal_handler_complete = false;
   int expected_frame_count = 0;
@@ -98,7 +113,7 @@ static void verify_unwind_data(const UnwindData& unwind_data) {
   EXPECT_EQ(unwind_data.handler_frame_count + 1, unwind_data.handler_one_deeper_frame_count);
 }
 
-static void noinline UnwindTest() {
+static void noinline SignalUnwindTest() {
   g_unwind_data = {};
 
   _Unwind_Backtrace(FrameCounter, &g_unwind_data.expected_frame_count);
@@ -114,12 +129,12 @@ static void noinline UnwindTest() {
 TEST(stack_unwinding, unwind_through_signal_frame) {
   ScopedSignalHandler ssh(SIGUSR1, UnwindSignalHandler);
 
-  UnwindTest();
+  SignalUnwindTest();
 }
 
 // On LP32, the SA_SIGINFO flag gets you __restore_rt instead of __restore.
 TEST(stack_unwinding, unwind_through_signal_frame_SA_SIGINFO) {
   ScopedSignalHandler ssh(SIGUSR1, UnwindSignalHandler, SA_SIGINFO);
 
-  UnwindTest();
+  SignalUnwindTest();
 }