commit 1a5b59386d1512a0488c9af0bf921de6fcdb7669
author Bart Van Assche <bvanassche@google.com> Tue Oct 25 17:07:36 2022 -0700
committer Bart Van Assche <bvanassche@google.com> Thu Oct 27 08:07:26 2022 -0700
tree 3cf47d17452e820937dbe81e0d92e22660e3f73f
parent 874448f4aa562aa1d882ea398383b332110bcfc3

init: Fix HandleSignalFd()

There are two bugs in HandleSignalFd():
* If the one_off argument is true and if no data is read from the
  signalfd, 'siginfo' is left uninitialized and used in the switch
  statement in HandleSignalFd().
* The PLOG() statement in the switch statement should be a LOG()
  statement since it does not report a failed system call.

This CL has been tested by changing kDiagnosticTimeout locally from 10s
into 100ms.

Change-Id: I0e488dd95bc13e1befaef770c0748d1d47f6e431
Signed-off-by: Bart Van Assche <bvanassche@google.com>

init/init.cpp

diff --git a/init/init.cpp b/init/init.cpp
index 4ca351c..57397b5 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -747,6 +747,9 @@
     do {
         ssize_t bytes_read = TEMP_FAILURE_RETRY(read(signal_fd, &siginfo, sizeof(siginfo)));
         if (bytes_read < 0 && errno == EAGAIN) {
+            if (one_off) {
+                return;
+            }
             auto now = std::chrono::steady_clock::now();
             std::chrono::duration<double> waited = now - started;
             if (waited >= kDiagnosticTimeout) {
@@ -772,7 +775,7 @@
             HandleSigtermSignal(siginfo);
             break;
         default:
-            PLOG(ERROR) << "signal_fd: received unexpected signal " << siginfo.ssi_signo;
+            LOG(ERROR) << "signal_fd: received unexpected signal " << siginfo.ssi_signo;
             break;
     }
 }