Merge "Revert "add a fortified implementation of getcwd""

libc/Android.mk

@@ -72,7 +72,6 @@ libc_common_src_files += \
     bionic/__fgets_chk.cpp \
     bionic/__fread_chk.cpp \
     bionic/__fwrite_chk.cpp \
-    bionic/__getcwd_chk.cpp \
     bionic/__memchr_chk.cpp \
     bionic/__memmove_chk.cpp \
     bionic/__memrchr_chk.cpp \

libc/bionic/__getcwd_chk.cpp

@@ -1,40 +0,0 @@
-/*
- * Copyright (C) 2015 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.
- */
-
-#undef _FORTIFY_SOURCE
-
-#include <unistd.h>
-#include "private/libc_logging.h"
-
-extern char* __getcwd_chk(char* buf, size_t len, size_t buflen) {
-  if (__predict_false(len > buflen)) {
-    __fortify_chk_fail("getcwd: prevented write past end of buffer", 0);
-  }
-
-  return getcwd(buf, len);
-}

libc/include/unistd.h

@@ -224,10 +224,6 @@ extern int   tcsetpgrp(int fd, pid_t _pid);
     } while (_rc == -1 && errno == EINTR); \
     _rc; })
 
-extern char* __getcwd_chk(char*, size_t, size_t);
-__errordecl(__getcwd_dest_size_error, "getcwd called with size bigger than destination");
-extern char* __getcwd_real(char*, size_t) __RENAME(getcwd);
-
 extern ssize_t __pread_chk(int, void*, size_t, off_t, size_t);
 __errordecl(__pread_dest_size_error, "pread called with size bigger than destination");
 __errordecl(__pread_count_toobig_error, "pread called with count > SSIZE_MAX");
@@ -255,37 +251,6 @@ extern ssize_t __readlinkat_real(int dirfd, const char*, char*, size_t) __RENAME
 
 #if defined(__BIONIC_FORTIFY)
 
-__BIONIC_FORTIFY_INLINE
-char* getcwd(char* buf, size_t size) {
-    size_t bos = __bos(buf);
-
-#if defined(__clang__)
-    /*
-     * Work around LLVM's incorrect __builtin_object_size implementation here
-     * to avoid needing the workaround in the __getcwd_chk ABI forever.
-     *
-     * https://llvm.org/bugs/show_bug.cgi?id=23277
-     */
-    if (buf == NULL) {
-        bos = __BIONIC_FORTIFY_UNKNOWN_SIZE;
-    }
-#else
-    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
-        return __getcwd_real(buf, size);
-    }
-
-    if (__builtin_constant_p(size) && (size > bos)) {
-        __getcwd_dest_size_error();
-    }
-
-    if (__builtin_constant_p(size) && (size <= bos)) {
-        return __getcwd_real(buf, size);
-    }
-#endif
-
-    return __getcwd_chk(buf, size, bos);
-}
-
 #if defined(__USE_FILE_OFFSET64)
 #define __PREAD_PREFIX(x) __pread64_ ## x
 #else

libc/libc.map

@@ -1336,7 +1336,6 @@ LIBC_N {
   global:
     __fread_chk;
     __fwrite_chk;
-    __getcwd_chk;
     getgrgid_r;
     getgrnam_r;
 } LIBC;

tests/fortify_compilation_test.cpp

@@ -262,11 +262,3 @@ void test_fwrite_too_big() {
   // clang should emit a warning, but doesn't
   fwrite(buf, 1, 5, stdout);
 }
-
-void test_getcwd() {
-  char buf[4];
-  // NOLINTNEXTLINE(whitespace/line_length)
-  // GCC: error: call to '__getcwd_dest_size_error' declared with attribute error: getcwd called with size bigger than destination
-  // clang should emit a warning, but doesn't
-  getcwd(buf, 5);
-}

tests/fortify_test.cpp

@@ -623,12 +623,6 @@ TEST_F(DEATHTEST, FD_ISSET_2_fortified) {
   ASSERT_FORTIFY(FD_ISSET(0, set));
 }
 
-TEST_F(DEATHTEST, getcwd_fortified) {
-  char buf[1];
-  size_t ct = atoi("2"); // prevent optimizations
-  ASSERT_FORTIFY(getcwd(buf, ct));
-}
-
 TEST_F(DEATHTEST, pread_fortified) {
   char buf[1];
   size_t ct = atoi("2"); // prevent optimizations