Change _stdio_handles_locking into _caller_handles_locking.
It is reported by tsan that funlockfile() can unlock an unlocked mutex.
It happens when printf() is called before fopen() or other stdio stuff.
As FLOCKFILE(fp) is called before __sinit(), _stdio_handles_locking is false,
and _FLOCK(fp) will not be locked. But then cantwrite(fp) in __vfprintf()
calls__sinit(), which makes _stdio_handles_locking become true, and
FUNLOCKFILE(fp) unlocks _FLOCK(fp).
Change _stdio_handles_locking into _caller_handles_locking,
so __sinit() won't change its value. Add test due to my previous fault.
Bug: 25392375
Change-Id: I483e3c3cdb28da65e62f1fd9615bf58c5403b4dd
diff --git a/tests/pthread_test.cpp b/tests/pthread_test.cpp
index e237d26..284af8f 100755
--- a/tests/pthread_test.cpp
+++ b/tests/pthread_test.cpp
@@ -30,12 +30,8 @@
#include <unwind.h>
#include <atomic>
-#include <regex>
#include <vector>
-#include <base/file.h>
-#include <base/stringprintf.h>
-
#include "private/bionic_macros.h"
#include "private/ScopeGuard.h"
#include "BionicDeathTest.h"
@@ -43,8 +39,6 @@
#include "utils.h"
-extern "C" pid_t gettid();
-
TEST(pthread, pthread_key_create) {
pthread_key_t key;
ASSERT_EQ(0, pthread_key_create(&key, NULL));
@@ -721,23 +715,6 @@
ASSERT_EQ(0, pthread_rwlock_destroy(&l));
}
-static void WaitUntilThreadSleep(std::atomic<pid_t>& tid) {
- while (tid == 0) {
- usleep(1000);
- }
- std::string filename = android::base::StringPrintf("/proc/%d/stat", tid.load());
- std::regex regex {R"(\s+S\s+)"};
-
- while (true) {
- std::string content;
- ASSERT_TRUE(android::base::ReadFileToString(filename, &content));
- if (std::regex_search(content, regex)) {
- break;
- }
- usleep(1000);
- }
-}
-
struct RwlockWakeupHelperArg {
pthread_rwlock_t lock;
enum Progress {
diff --git a/tests/stdio_ext_test.cpp b/tests/stdio_ext_test.cpp
index c95cbbd..7872567 100644
--- a/tests/stdio_ext_test.cpp
+++ b/tests/stdio_ext_test.cpp
@@ -30,6 +30,7 @@
#include <locale.h>
#include "TemporaryFile.h"
+#include "utils.h"
TEST(stdio_ext, __fbufsize) {
FILE* fp = fopen("/proc/version", "r");
@@ -140,3 +141,24 @@
ASSERT_EQ(FSETLOCKING_INTERNAL, __fsetlocking(fp, FSETLOCKING_QUERY));
fclose(fp);
}
+
+static void LockingByCallerHelper(std::atomic<pid_t>* pid) {
+ *pid = gettid();
+ flockfile(stdout);
+ funlockfile(stdout);
+}
+
+TEST(stdio_ext, __fsetlocking_BYCALLER) {
+ // Check if users can use flockfile/funlockfile to protect stdio operations.
+ int old_state = __fsetlocking(stdout, FSETLOCKING_BYCALLER);
+ flockfile(stdout);
+ pthread_t thread;
+ std::atomic<pid_t> pid(0);
+ ASSERT_EQ(0, pthread_create(&thread, nullptr,
+ reinterpret_cast<void* (*)(void*)>(LockingByCallerHelper), &pid));
+ WaitUntilThreadSleep(pid);
+ funlockfile(stdout);
+
+ ASSERT_EQ(0, pthread_join(thread, nullptr));
+ __fsetlocking(stdout, old_state);
+}
diff --git a/tests/utils.h b/tests/utils.h
index 53cf6b6..9e77f24 100644
--- a/tests/utils.h
+++ b/tests/utils.h
@@ -18,6 +18,14 @@
#define __TEST_UTILS_H
#include <inttypes.h>
#include <sys/mman.h>
+#include <unistd.h>
+
+#include <atomic>
+#include <string>
+#include <regex>
+
+#include <base/file.h>
+#include <base/stringprintf.h>
#include "private/ScopeGuard.h"
@@ -82,4 +90,23 @@
}
};
+extern "C" pid_t gettid();
+
+static inline void WaitUntilThreadSleep(std::atomic<pid_t>& tid) {
+ while (tid == 0) {
+ usleep(1000);
+ }
+ std::string filename = android::base::StringPrintf("/proc/%d/stat", tid.load());
+ std::regex regex {R"(\s+S\s+)"};
+
+ while (true) {
+ std::string content;
+ ASSERT_TRUE(android::base::ReadFileToString(filename, &content));
+ if (std::regex_search(content, regex)) {
+ break;
+ }
+ usleep(1000);
+ }
+}
+
#endif