* apt-pkg/deb/dpkgpm.cc:

  - stdin redirected to /dev/null takes all CPU (Closes: #569488)
    Thanks to Aurelien Jarno for providing (again) a patch!

apt-pkg/deb/dpkgpm.cc

@@ -1005,7 +1005,7 @@ bool pkgDPkgPM::Go(int OutStatusFd)
 
 	 // wait for input or output here
 	 FD_ZERO(&rfds);
-	 if (!stdin_is_dev_null)
+	 if (master >= 0 && !stdin_is_dev_null)
 	    FD_SET(0, &rfds); 
 	 FD_SET(_dpkgin, &rfds);
 	 if(master >= 0)

debian/changelog

@@ -21,6 +21,9 @@ apt (0.7.26) UNRELEASED; urgency=low
     - add APT::FTPArchive::AlwaysStat to disable the too aggressive
       caching if versions are build multiply times (not recommend)
       Patch by Christoph Goehre, thanks! (Closes: #463260)
+  * apt-pkg/deb/dpkgpm.cc:
+    - stdin redirected to /dev/null takes all CPU (Closes: #569488)
+      Thanks to Aurelien Jarno for providing (again) a patch!
 
   [ Ivan Masár ]
   * Slovak translation update. Closes: #568294