commit 2356c93d391c1948b3abb7602da3d97bd8b289f2
author George Burgess IV <gbiv@google.com> Thu Jun 06 17:18:13 2019 -0700
committer George Burgess IV <gbiv@google.com> Thu Jun 13 23:26:02 2019 -0700
tree a490fc205ecbbd2f21b93f0102a806ccc1a075de
parent 77f99aaf58b944b23f2cfb38fce08a98feabe93f

fortify: add bit checking for open(at)?64 functions

This also adds _2-variants for these functions, for extra glorious
checking

Bug: 131861088
Test: mma
Change-Id: I80475ff4bb220c0c47894e9532426f53412f176f

libc/bionic/open.cpp

diff --git a/libc/bionic/open.cpp b/libc/bionic/open.cpp
index 222e5d3..df5ab21 100644
--- a/libc/bionic/open.cpp
+++ b/libc/bionic/open.cpp
@@ -70,6 +70,7 @@
   if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
   return __openat(AT_FDCWD, pathname, force_O_LARGEFILE(flags), 0);
 }
+__strong_alias(__open64_2, __open_2);
 
 int openat(int fd, const char *pathname, int flags, ...) {
   mode_t mode = 0;
@@ -89,3 +90,4 @@
   if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
   return __openat(fd, pathname, force_O_LARGEFILE(flags), 0);
 }
+__strong_alias(__openat64_2, __openat_2);

libc/include/bits/fortify/fcntl.h

diff --git a/libc/include/bits/fortify/fcntl.h b/libc/include/bits/fortify/fcntl.h
index e7f2c82..4bb441e 100644
--- a/libc/include/bits/fortify/fcntl.h
+++ b/libc/include/bits/fortify/fcntl.h
@@ -92,6 +92,52 @@
 }
 #endif /* __ANDROID_API__ >= __ANDROID_API_J_MR1__ */
 
+#if __ANDROID_API__ >= __ANDROID_API_R__
+int __open64_2(const char*, int) __INTRODUCED_IN(30);
+int __openat64_2(int, const char*, int) __INTRODUCED_IN(30);
+int __open64_real(const char* __path, int __flags, ...) __RENAME(open64);
+int __openat64_real(int, const char*, int, ...) __RENAME(openat64);
+
+__BIONIC_ERROR_FUNCTION_VISIBILITY
+int open64(const char* pathname, int flags, mode_t modes, ...) __overloadable
+        __errorattr(__open_too_many_args_error);
+
+__BIONIC_FORTIFY_INLINE
+int open64(const char* const __pass_object_size pathname, int flags)
+        __overloadable
+        __clang_error_if(__open_modes_useful(flags), "'open64' " __open_too_few_args_error) {
+    return __open64_2(pathname, flags);
+}
+
+__BIONIC_FORTIFY_INLINE
+int open64(const char* const __pass_object_size pathname, int flags, mode_t modes)
+        __overloadable
+        __clang_warning_if(!__open_modes_useful(flags) && modes,
+                           "'open64' " __open_useless_modes_warning) {
+    return __open64_real(pathname, flags, modes);
+}
+
+__BIONIC_ERROR_FUNCTION_VISIBILITY
+int openat64(int dirfd, const char* pathname, int flags, mode_t modes, ...)
+        __overloadable
+        __errorattr(__open_too_many_args_error);
+
+__BIONIC_FORTIFY_INLINE
+int openat64(int dirfd, const char* const __pass_object_size pathname, int flags)
+        __overloadable
+        __clang_error_if(__open_modes_useful(flags), "'openat64' " __open_too_few_args_error) {
+    return __openat64_2(dirfd, pathname, flags);
+}
+
+__BIONIC_FORTIFY_INLINE
+int openat64(int dirfd, const char* const __pass_object_size pathname, int flags, mode_t modes)
+        __overloadable
+        __clang_warning_if(!__open_modes_useful(flags) && modes,
+                           "'openat64' " __open_useless_modes_warning) {
+    return __openat64_real(dirfd, pathname, flags, modes);
+}
+#endif /* __ANDROID_API__ >= __ANDROID_API_R__ */
+
 #undef __open_too_many_args_error
 #undef __open_too_few_args_error
 #undef __open_useless_modes_warning

libc/libc.map.txt

diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index 424c8f3..b12df56 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1482,6 +1482,8 @@
 
 LIBC_R { # introduced=R
   global:
+    __open64_2;
+    __openat64_2;
     call_once;
     cnd_broadcast;
     cnd_destroy;