Simplify __stack_chk_fail, and fix it so we get debuggerd stack traces.

Bug: 2487269
Change-Id: Iec5e470fc22cd9108404f634a9d4baa2c7b7f58f

libc/Android.mk

@@ -725,7 +725,7 @@ WITH_MALLOC_CHECK_LIBC_A := $(strip $(WITH_MALLOC_CHECK_LIBC_A))
 
 include $(CLEAR_VARS)
 
-LOCAL_SRC_FILES := bionic/ssp.cpp
+LOCAL_SRC_FILES := bionic/__stack_chk_fail.cpp bionic/__stack_chk_guard.cpp
 LOCAL_CFLAGS := $(libc_common_cflags) -fno-stack-protector -Werror
 LOCAL_C_INCLUDES := $(libc_common_c_includes)
 LOCAL_MODULE := libbionic_ssp

libc/bionic/__stack_chk_fail.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+
+#include "bionic_ssp.h"
+#include "debug_format.h"
+#include "logd.h"
+
+void __stack_chk_fail() {
+  __libc_format_log(ANDROID_LOG_FATAL, "libc", "stack corruption detected");
+  abort();
+}

libc/bionic/__stack_chk_guard.cpp

@@ -26,17 +26,9 @@
  * SUCH DAMAGE.
  */
 
-#include <ctype.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/auxv.h>
-#include <unistd.h>
-
 #include "bionic_ssp.h"
-#include "logd.h"
+
+#include <sys/auxv.h>
 
 uintptr_t __stack_chk_guard = 0;
 
@@ -44,40 +36,3 @@ static void __attribute__((constructor)) __init_stack_check_guard() {
   // AT_RANDOM is a pointer to 16 bytes of randomness on the stack.
   __stack_chk_guard = *reinterpret_cast<uintptr_t*>(getauxval(AT_RANDOM));
 }
-
-// This is the crash handler.
-// Does a best effort at logging and calls _exit to terminate
-// the process immediately (without atexit handlers, etc.).
-void __stack_chk_fail() {
-  // Immediately block all (but SIGABRT) signal handlers from running code.
-  sigset_t sigmask;
-  sigfillset(&sigmask);
-  sigdelset(&sigmask, SIGABRT);
-  sigprocmask(SIG_BLOCK, &sigmask, NULL);
-
-  // Use /proc/self/exe link to obtain the program name for logging
-  // purposes. If it's not available, we set it to "<unknown>".
-  char path[PATH_MAX];
-  int count;
-  if ((count = readlink("/proc/self/exe", path, sizeof(path) - 1)) == -1) {
-    strlcpy(path, "<unknown>", sizeof(path));
-  } else {
-    path[count] = '\0';
-  }
-
-  // Do a best effort at logging.
-  __libc_android_log_write(ANDROID_LOG_FATAL, path, "stack corruption detected: aborted");
-
-  // Make sure there is no default action for SIGABRT.
-  struct sigaction sa;
-  memset(&sa, 0, sizeof(sa));
-  sigemptyset(&sa.sa_mask);
-  sa.sa_flags = 0;
-  sa.sa_handler = SIG_DFL;
-  sigaction(SIGABRT, &sa, NULL);
-
-  // Terminate the process and exit immediately.
-  kill(getpid(), SIGABRT);
-
-  _exit(127);
-}

libc/bionic/pthread.c

@@ -36,7 +36,6 @@
 #include "bionic_atomic_inline.h"
 #include "bionic_futex.h"
 #include "bionic_pthread.h"
-#include "bionic_ssp.h"
 #include "bionic_tls.h"
 #include "pthread_internal.h"
 #include "thread_private.h"

libc/private/bionic_ssp.h

@@ -29,6 +29,9 @@
 #ifndef _PRIVATE_SSP_H
 #define _PRIVATE_SSP_H
 
+#include <stdint.h>
+#include <sys/cdefs.h>
+
 __BEGIN_DECLS
 
 /* GCC uses this on ARM and MIPS; we use it on x86 to set the guard in TLS. */

tests/stack_protector_test.cpp

@@ -36,7 +36,7 @@ pid_t gettid() { return syscall(__NR_gettid); }
 
 #ifdef __i386__
 
-// For x86, bionic and glibc have per-thread stack guard values.
+// For x86, bionic and glibc have per-thread stack guard values (all identical).
 
 static uint32_t GetGuardFromTls() {
   uint32_t guard;