1 files changed, 18 insertions, 14 deletions

diff --git a/apt-inst/contrib/extracttar.cc b/apt-inst/contrib/extracttar.cc
index 49ed5db56..41301d1a6 100644
--- a/apt-inst/contrib/extracttar.cc
+++ b/apt-inst/contrib/extracttar.cc
@@ -6,7 +6,7 @@
    Extract a Tar - Tar Extractor
 
    Some performance measurements showed that zlib performed quite poorly
-   in comparision to a forked gzip process. This tar extractor makes use
+   in comparison to a forked gzip process. This tar extractor makes use
    of the fact that dup'd file descriptors have the same seek pointer
    and that gzip will not read past the end of a compressed stream, 
    even if there is more data. We use the dup property to track extraction
@@ -111,6 +111,12 @@ bool ExtractTar::Done(bool Force)
    gzip will efficiently ignore the extra bits. */
 bool ExtractTar::StartGzip()
 {
+   if (DecompressProg.empty())
+   {
+      InFd.OpenDescriptor(File.Fd(), FileFd::ReadOnly, FileFd::None, false);
+      return true;
+   }
+
    int Pipes[2];
    if (pipe(Pipes) != 0)
       return _error->Errno("pipe",_("Failed to create pipes"));
@@ -161,8 +167,8 @@ bool ExtractTar::Go(pkgDirStream &Stream)
       return false;
    
    // Loop over all blocks
-   string LastLongLink;
-   string LastLongName;
+   string LastLongLink, ItemLink;
+   string LastLongName, ItemName;
    while (1)
    {
       bool BadRecord = false;      
@@ -208,25 +214,23 @@ bool ExtractTar::Go(pkgDirStream &Stream)
 	  StrToNum(Tar->Major,Itm.Major,sizeof(Tar->Major),8) == false ||
 	  StrToNum(Tar->Minor,Itm.Minor,sizeof(Tar->Minor),8) == false)
 	 return _error->Error(_("Corrupted archive"));
-      
-      // Grab the filename
+
+      // Grab the filename and link target: use last long name if one was
+      // set, otherwise use the header value as-is, but remember that it may
+      // fill the entire 100-byte block and needs to be zero-terminated.
+      // See Debian Bug #689582.
       if (LastLongName.empty() == false)
 	 Itm.Name = (char *)LastLongName.c_str();
       else
-      {
-	 Tar->Name[sizeof(Tar->Name)-1] = 0;
-	 Itm.Name = Tar->Name;
-      }      
+	 Itm.Name = (char *)ItemName.assign(Tar->Name, sizeof(Tar->Name)).c_str();
       if (Itm.Name[0] == '.' && Itm.Name[1] == '/' && Itm.Name[2] != 0)
 	 Itm.Name += 2;
-      
-      // Grab the link target
-      Tar->Name[sizeof(Tar->LinkName)-1] = 0;
-      Itm.LinkTarget = Tar->LinkName;
 
       if (LastLongLink.empty() == false)
 	 Itm.LinkTarget = (char *)LastLongLink.c_str();
-      
+      else
+	 Itm.LinkTarget = (char *)ItemLink.assign(Tar->LinkName, sizeof(Tar->LinkName)).c_str();
+
       // Convert the type over
       switch (Tar->LinkFlag)
       {