[bug-sourceinstall] patch for memory access in srcinst.c:_init_state

[Brian Gough]

Hello.  I noticed a memory error in _init_state(), where h is obtained
from getenv() and on exit there is an attempt to free it. The patch
below fixes it with a srcinst_strdup() to make a copy that can be
freed.

Also for safety it initializes the arrays with sizeof() since they are
actually of size "N+1" rather than N (although this does not seem to
matter in practice).

Index: srcinst.c
===================================================================
RCS file: /sources/sourceinstall/sourceinstall2/libsrcinst/srcinst.c,v
retrieving revision 1.26
diff -u -r1.26 srcinst.c
--- srcinst.c   7 Dec 2009 00:42:01 -0000       1.26
+++ srcinst.c   8 Jan 2010 20:17:51 -0000
@@ -430,12 +434,12 @@
 {
     char buffer[SRCINST_BUFSIZE];
     char *h;
-    memset(_srcinst_state.files, 0, sizeof(char *) * SRCINST_FILE_N);
-    memset(_srcinst_state.dirs, 0, sizeof(char *) * SRCINST_DIR_N);
+    memset(_srcinst_state.files, 0, sizeof(_srcinst_state.files));
+    memset(_srcinst_state.dirs, 0, sizeof(_srcinst_state.dirs));

     if ((h = getenv("SOURCEINSTALLDIR")) && *h) {
        /* use SOURCEINSTALLDIR env variable */
-       _srcinst_state.dirs[SRCINST_DIR_CFG] = h;
+       _srcinst_state.dirs[SRCINST_DIR_CFG] = srcinst_strdup(h);

     } else if ((h = getenv("HOME")) && *h) {
        /* use HOME env variable, append .sourceinstall */