commit 156d5a8ae93c6515919dd6706481991c7c0dc600
author George Burgess IV <gbiv@google.com> Fri Feb 10 13:56:22 2017 -0800
committer George Burgess IV <gbiv@google.com> Fri Feb 10 18:14:43 2017 -0800
tree babd491737f6965d7c6910869b435e5e47cf7cdc
parent e86a8d605b3df0c396e23ee02933c76d7040a73b

Match __bos0 to __pass_object_size0 in FORTIFY

pass_object_size(N) forwards the result of __builtin_object_size(param,
N) to a function. So, a function that looks like:

  size_t foo(void *const p __pass_object_size) { return __bos0(p); }
  int bar = foo(baz);

would effectively be turned into

  size_t foo(void *const p, size_t sz) { return sz; }
  int bar = foo(baz, __bos(baz)); // note that this is not __bos0

This is bad, since if we're using __bos0, we want more relaxed
objectsize checks.

__bos0 should be more permissive than __bos in all cases, so this
change Should Be Fine™.

This change also makes GCC and clang share another function's
implementation (recv). I just realized we need to add special
diagnostic-related overloads bits for clang to it, but I can do that in
another patch.

Bug: None
Test: Bullhead builds and boots; CtsBionicTestCases passes.
Change-Id: I6818d0041328ab5fd0946a1e57321a977c1e1250

libc/include/unistd.h

diff --git a/libc/include/unistd.h b/libc/include/unistd.h
index b3f8c11..7c6125a 100644
--- a/libc/include/unistd.h
+++ b/libc/include/unistd.h
@@ -322,7 +322,7 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t pread(int fd, void* const __pass_object_size buf, size_t count,
+ssize_t pread(int fd, void* const __pass_object_size0 buf, size_t count,
               off_t offset) __overloadable {
     size_t bos = __bos0(buf);
 
@@ -343,7 +343,7 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t pread64(int fd, void* const __pass_object_size buf, size_t count,
+ssize_t pread64(int fd, void* const __pass_object_size0 buf, size_t count,
                 off64_t offset) __overloadable {
     size_t bos = __bos0(buf);
 
@@ -368,7 +368,7 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t pwrite(int fd, const void* const __pass_object_size buf, size_t count,
+ssize_t pwrite(int fd, const void* const __pass_object_size0 buf, size_t count,
                off_t offset) __overloadable {
     size_t bos = __bos0(buf);
 
@@ -391,8 +391,8 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t pwrite64(int fd, const void* const __pass_object_size buf, size_t count,
-                 off64_t offset) __overloadable {
+ssize_t pwrite64(int fd, const void* const __pass_object_size0 buf,
+                 size_t count, off64_t offset) __overloadable {
     size_t bos = __bos0(buf);
 
     if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
@@ -413,7 +413,7 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t read(int fd, void* const __pass_object_size buf, size_t count)
+ssize_t read(int fd, void* const __pass_object_size0 buf, size_t count)
         __overloadable {
     size_t bos = __bos0(buf);
 
@@ -434,7 +434,7 @@
         __error_if_overflows_objectsize(count, __bos0(buf));
 
 __BIONIC_FORTIFY_INLINE
-ssize_t write(int fd, const void* const __pass_object_size buf, size_t count)
+ssize_t write(int fd, const void* const __pass_object_size0 buf, size_t count)
         __overloadable {
     size_t bos = __bos0(buf);