Fix a double-free by setting scontext to NULL after calling freecon

Based on a patch by Russell Coker. Closes: #474339

ChangeLog

@@ -1,3 +1,8 @@
+2008-04-12  Russell Coker <russell@coker.com.au>,
+            Guillem Jover  <guillem@debian.org>
+
+	* src/archives.c (tarobject): Set scontext to NULL after freecon.
+
 2008-04-10  Sven Joachim  <svenjoac@gmx.de>
 
 	* src/trigcmd.c: Fix typo.

THANKS

@@ -142,6 +142,7 @@ Robert Luberda <robert@debian.org>
 Robert Millan <rmh@debian.org>
 Roderick Schertler <roderick@argon.org>
 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+Russell Coker <russell@coker.com.au>
 SZERVÁC Attila <sas@321.hu>
 Samuel Thibault <samuel.thibault@ens-lyon.org>
 Scott Barker <scott@mostlylinux.ab.ca>

debian/changelog

@@ -1,5 +1,9 @@
 dpkg (1.14.19) UNRELEASED; urgency=low
 
+  [ Guillem Jover ]
+  * Fix a double-free by setting scontext to NULL after calling freecon.
+    Based on a patch by Russell Coker. Closes: #474339
+
   [ Updated dpkg translations ]
   * Galician (Jacobo Tarrio).
   * German (Sven Joachim).

src/archives.c

@@ -801,6 +801,7 @@ int tarobject(struct TarInfo *ti) {
        if(setfscreatecon(scontext) < 0)
          perror("Error setting security context for next file object:");
        freecon(scontext);
+       scontext = NULL;
      }
         
 #endif /* WITH_SELINUX */