tequilaOS/platform_bionic
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

libc fortify: warn on open() with useless mode bits

Browse source 
Bug: 64132680
Test: checkbuild on bullhead internal master; no new CtsBionicTestCases
fail.

Change-Id: I98762bbee0ecdd7b4ffc21135992f2eed320317f
This commit is contained in:
George Burgess IV 2017-08-03 17:11:35 -07:00
parent 26c59f7082
commit 4e37d53f29
2 changed files with 20 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
libc/include/bits/fortify/fcntl.h
View file

@ -41,6 +41,9 @@ int __openat_real(int, const char*, int, ...) __RENAME(openat);
#if defined(__BIONIC_FORTIFY)
#define __open_too_many_args_error "too many arguments"
#define __open_too_few_args_error "called with O_CREAT, but missing mode"
#define __open_useless_modes_warning "has superfluous mode bits; missing O_CREAT?"
/* O_TMPFILE shares bits with O_DIRECTORY. */
#define __open_modes_useful(flags) (((flags) & O_CREAT) || ((flags) & O_TMPFILE) == O_TMPFILE)
#if defined(__clang__)
#if __ANDROID_API__ >= __ANDROID_API_J_MR1__
@ -62,7 +65,10 @@ int open(const char* const __pass_object_size pathname, int flags)
}
__BIONIC_FORTIFY_INLINE
int open(const char* const __pass_object_size pathname, int flags, mode_t modes) __overloadable {
int open(const char* const __pass_object_size pathname, int flags, mode_t modes)
__overloadable
__clang_warning_if(!__open_modes_useful(flags) && modes,
"'open' " __open_useless_modes_warning) {
return __open_real(pathname, flags, modes);
}
@ -72,16 +78,17 @@ int openat(int dirfd, const char* pathname, int flags, mode_t modes, ...)
__errorattr(__open_too_many_args_error);
__BIONIC_FORTIFY_INLINE
int openat(int dirfd, const char* const __pass_object_size pathname,
int flags)
int openat(int dirfd, const char* const __pass_object_size pathname, int flags)
__overloadable
__clang_error_if(flags & O_CREAT, "'openat' " __open_too_few_args_error) {
return __openat_2(dirfd, pathname, flags);
}
__BIONIC_FORTIFY_INLINE
int openat(int dirfd, const char* const __pass_object_size pathname, int flags,
mode_t modes) __overloadable {
int openat(int dirfd, const char* const __pass_object_size pathname, int flags, mode_t modes)
__overloadable
__clang_warning_if(!__open_modes_useful(flags) && modes,
"'openat' " __open_useless_modes_warning) {
return __openat_real(dirfd, pathname, flags, modes);
}
#endif /* __ANDROID_API__ >= __ANDROID_API_J_MR1__ */
@ -134,4 +141,6 @@ int openat(int dirfd, const char* pathname, int flags, ...) {
#undef __open_too_many_args_error
#undef __open_too_few_args_error
#undef __open_useless_modes_warning
#undef __open_modes_useful
#endif /* defined(__BIONIC_FORTIFY) */

6
tests/fortify_compilation_test.cpp
View file

@ -222,6 +222,12 @@ void test_open() {
// GCC: error: call to '__creat_too_many_args' declared with attribute error: too many arguments
// CLANG: error: call to unavailable function 'open': too many arguments
open("/dev/null", O_CREAT, 0, 0);
// CLANG: warning: 'open' has superfluous mode bits; missing O_CREAT?
open("/dev/null", O_RDONLY, 0644);
// CLANG: warning: 'open' has superfluous mode bits; missing O_CREAT?
open("/dev/null", O_DIRECTORY, 0644);
}
void test_poll() {