Merge "Only one crashing thread should contact debuggerd."
diff --git a/linker/debugger.cpp b/linker/debugger.cpp
index c889544..6fe9524 100644
--- a/linker/debugger.cpp
+++ b/linker/debugger.cpp
@@ -30,9 +30,11 @@
#include <errno.h>
#include <inttypes.h>
+#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#include <sys/socket.h>
@@ -212,6 +214,23 @@
return;
}
+ // Mutex to prevent multiple crashing threads from trying to talk
+ // to debuggerd at the same time.
+ static pthread_mutex_t crash_mutex = PTHREAD_MUTEX_INITIALIZER;
+ int ret = pthread_mutex_trylock(&crash_mutex);
+ if (ret != 0) {
+ if (ret == EBUSY) {
+ __libc_format_log(ANDROID_LOG_INFO, "libc",
+ "Another thread has contacted debuggerd first, stop and wait for process to die.");
+ // This will never complete since the lock is never released.
+ pthread_mutex_lock(&crash_mutex);
+ } else {
+ __libc_format_log(ANDROID_LOG_INFO, "libc",
+ "pthread_mutex_trylock failed: %s", strerror(ret));
+ }
+ return;
+ }
+
int s = socket_abstract_client(DEBUGGER_SOCKET_NAME, SOCK_STREAM | SOCK_CLOEXEC);
if (s == -1) {
__libc_format_log(ANDROID_LOG_FATAL, "libc", "Unable to open connection to debuggerd: %s",
@@ -228,7 +247,7 @@
msg.tid = gettid();
msg.abort_msg_address = reinterpret_cast<uintptr_t>(g_abort_message);
msg.original_si_code = (info != nullptr) ? info->si_code : 0;
- int ret = TEMP_FAILURE_RETRY(write(s, &msg, sizeof(msg)));
+ ret = TEMP_FAILURE_RETRY(write(s, &msg, sizeof(msg)));
if (ret == sizeof(msg)) {
char debuggerd_ack;
ret = TEMP_FAILURE_RETRY(read(s, &debuggerd_ack, 1));