commit 3b868b243692b74705c65ccd6de13b55799d9499
Author: Bryn M. Reeves <bmr@redhat.com>
Date:   Thu May 23 15:32:07 2013 +0100

    Always use '-f-' when calling tar
    
    The tar program evaluates TAPE to determine the default tape
    device. This means that when sos is run with this environment
    variable set it may write the report data to the tape device
    and fail to generate a correct archive.
    
    This may cause a loss of data from the tape device as well as
    a loss of diagnostic data.
    
    Signed-off-by: Bryn M. Reeves <bmr@redhat.com>

diff --git a/sos/policyredhat.py b/sos/policyredhat.py
index a93e92b..d19b9c2 100755
--- a/sos/policyredhat.py
+++ b/sos/policyredhat.py
@@ -268,7 +268,7 @@ class SosPolicy:
         if os.path.isfile("/usr/bin/xz"):
             self.report_file_ext = "tar.xz"
             self.renameResults("sosreport-%s-%s.%s" % (self.reportName, time.strftime("%Y%m%d%H%M%S"), self.report_file_ext))
-            cmd = "/bin/tar -c %s | /usr/bin/xz -1 > %s" % (os.path.basename(self.cInfo['dstroot']),self.report_file)
+            cmd = "/bin/tar -cf- %s | /usr/bin/xz -1 > %s" % (os.path.basename(self.cInfo['dstroot']),self.report_file)
             p = Popen(cmd, shell=True, bufsize=-1)
             sts = os.waitpid(p.pid, 0)[1]
         else: