Merge "debuggerd_handler: set PR_SET_PTRACER before running crash_dump." am:... (df53f4d0) · Commits · e / os / android_system_core

debuggerd/handler/debuggerd_handler.cpp

+16 −0

Original line number	Diff line number	Diff line
		@@ -500,6 +500,17 @@ static void debuggerd_signal_handler(int signal_number, siginfo_t* info, void* c
		fatal_errno("failed to set dumpable");
		}

		// On kernels with yama_ptrace enabled, also allow any process to attach.
		bool restore_orig_ptracer = true;
		if (prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) != 0) {
		if (errno == EINVAL) {
		// This kernel does not support PR_SET_PTRACER_ANY, or Yama is not enabled.
		restore_orig_ptracer = false;
		} else {
		fatal_errno("failed to set traceable");
		}
		}

		// Essentially pthread_create without CLONE_FILES, so we still work during file descriptor
		// exhaustion.
		pid_t child_pid =
		@@ -521,6 +532,11 @@ static void debuggerd_signal_handler(int signal_number, siginfo_t* info, void* c
		fatal_errno("failed to restore dumpable");
		}

		// Restore PR_SET_PTRACER to its original value.
		if (restore_orig_ptracer && prctl(PR_SET_PTRACER, 0) != 0) {
		fatal_errno("failed to restore traceable");
		}

		if (info->si_signo == DEBUGGER_SIGNAL) {
		// If the signal is fatal, don't unlock the mutex to prevent other crashing threads from
		// starting to dump right before our death.