Do not read stderr from proxy autodetection scripts

This fixes a regression introduced in
  commit 8f858d560e3b7b475c623c4e242d1edce246025a

  don't leak FD in AutoProxyDetect command return parsing

which accidentally made the proxy autodetection code also read
the scripts output on stderr, not only on stdout when it switched
the code from popen() to Popen().

Reported-By: Tim Small <tim@seoss.co.uk>
(cherry picked from commit 0ecceb5bb9cc8727c117195945b7116aceb984fe)

1 files changed, 7 insertions, 1 deletions

diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc
index 20ccaa1c6..df39ae160 100644
--- a/apt-pkg/contrib/fileutl.cc
+++ b/apt-pkg/contrib/fileutl.cc
@@ -2804,6 +2804,11 @@ bool Rename(std::string From, std::string To)				/*{{{*/
 									/*}}}*/
 bool Popen(const char* Args[], FileFd &Fd, pid_t &Child, FileFd::OpenMode Mode)/*{{{*/
 {
+   return Popen(Args, Fd, Child, Mode, true);
+}
+									/*}}}*/
+bool Popen(const char* Args[], FileFd &Fd, pid_t &Child, FileFd::OpenMode Mode, bool CaptureStderr)/*{{{*/
+{
    int fd;
    if (Mode != FileFd::ReadOnly && Mode != FileFd::WriteOnly)
       return _error->Error("Popen supports ReadOnly (x)or WriteOnly mode only");
@@ -2834,7 +2839,8 @@ bool Popen(const char* Args[], FileFd &Fd, pid_t &Child, FileFd::OpenMode Mode)/
       if(Mode == FileFd::ReadOnly)
       {
          dup2(fd, 1);
-         dup2(fd, 2);
+	 if (CaptureStderr == true)
+	    dup2(fd, 2);
       } else if(Mode == FileFd::WriteOnly)
          dup2(fd, 0);