debuggerd: remove maximum abort message length.
Let the logging implementation be the imposer of limits.
Bug: http://b/64759619
Test: debuggerd_test
Change-Id: I8bc73bf2301ce071668993b740880224846a4e75
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index 397ff2f..e410be9 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -354,7 +354,14 @@
int intercept_result;
unique_fd output_fd;
StartProcess([]() {
- android_set_abort_message("abort message goes here");
+ // Arrived at experimentally;
+ // logd truncates at 4062.
+ // strlen("Abort message: ''") is 17.
+ // That's 4045, but we also want a NUL.
+ char buf[4045 + 1];
+ memset(buf, 'x', sizeof(buf));
+ buf[sizeof(buf) - 1] = '\0';
+ android_set_abort_message(buf);
abort();
});
StartIntercept(&output_fd);
@@ -366,7 +373,7 @@
std::string result;
ConsumeFd(std::move(output_fd), &result);
- ASSERT_MATCH(result, R"(Abort message: 'abort message goes here')");
+ ASSERT_MATCH(result, R"(Abort message: 'x{4045}')");
}
TEST_F(CrasherTest, abort_message_backtrace) {
diff --git a/debuggerd/libdebuggerd/tombstone.cpp b/debuggerd/libdebuggerd/tombstone.cpp
index 140ef6d..55d6204 100644
--- a/debuggerd/libdebuggerd/tombstone.cpp
+++ b/debuggerd/libdebuggerd/tombstone.cpp
@@ -239,19 +239,23 @@
return;
}
- char msg[512];
- if (length >= sizeof(msg)) {
- _LOG(log, logtype::HEADER, "Abort message too long: claimed length = %zd\n", length);
+ // The length field includes the length of the length field itself.
+ if (length < sizeof(size_t)) {
+ _LOG(log, logtype::HEADER, "Abort message header malformed: claimed length = %zd\n", length);
return;
}
- if (!process_memory->ReadFully(address + sizeof(length), msg, length)) {
+ length -= sizeof(size_t);
+
+ std::vector<char> msg(length);
+ if (!process_memory->ReadFully(address + sizeof(length), &msg[0], length)) {
_LOG(log, logtype::HEADER, "Failed to read abort message: %s\n", strerror(errno));
return;
}
+ // The abort message should be null terminated already, but just in case...
msg[length] = '\0';
- _LOG(log, logtype::HEADER, "Abort message: '%s'\n", msg);
+ _LOG(log, logtype::HEADER, "Abort message: '%s'\n", &msg[0]);
}
static void dump_all_maps(log_t* log, BacktraceMap* map, Memory* process_memory, uint64_t addr) {
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index d153865..1ad1800 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -74,25 +74,22 @@
&& (log->crashed_tid == log->current_tid);
static bool write_to_kmsg = should_write_to_kmsg();
- char buf[512];
+ std::string msg;
va_list ap;
va_start(ap, fmt);
- vsnprintf(buf, sizeof(buf), fmt, ap);
+ android::base::StringAppendV(&msg, fmt, ap);
va_end(ap);
- size_t len = strlen(buf);
- if (len <= 0) {
- return;
- }
+ if (msg.empty()) return;
if (write_to_tombstone) {
- TEMP_FAILURE_RETRY(write(log->tfd, buf, len));
+ TEMP_FAILURE_RETRY(write(log->tfd, msg.c_str(), msg.size()));
}
if (write_to_logcat) {
- __android_log_buf_write(LOG_ID_CRASH, ANDROID_LOG_FATAL, LOG_TAG, buf);
+ __android_log_buf_write(LOG_ID_CRASH, ANDROID_LOG_FATAL, LOG_TAG, msg.c_str());
if (log->amfd_data != nullptr) {
- *log->amfd_data += buf;
+ *log->amfd_data += msg;
}
if (write_to_kmsg) {
@@ -100,11 +97,11 @@
if (kmsg_fd.get() >= 0) {
// Our output might contain newlines which would otherwise be handled by the android logger.
// Split the lines up ourselves before sending to the kernel logger.
- if (buf[len - 1] == '\n') {
- buf[len - 1] = '\0';
+ if (msg.back() == '\n') {
+ msg.back() = '\0';
}
- std::vector<std::string> fragments = android::base::Split(buf, "\n");
+ std::vector<std::string> fragments = android::base::Split(msg, "\n");
for (const std::string& fragment : fragments) {
static constexpr char prefix[] = "<3>DEBUG: ";
struct iovec iov[3];