Merge "debuggerd_handler: set PR_SET_PTRACER before running crash_dump." am: be10cae468 am: 66fa613dbb
am: 8b4cbf4a91
Change-Id: I5a6f242e96681be678a337d802b178ef92231dba
diff --git a/debuggerd/handler/debuggerd_handler.cpp b/debuggerd/handler/debuggerd_handler.cpp
index 96f3c7c..05e6efa 100644
--- a/debuggerd/handler/debuggerd_handler.cpp
+++ b/debuggerd/handler/debuggerd_handler.cpp
@@ -500,6 +500,17 @@
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 @@
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.