e_sys - address security concerns with environment and gdb

1. clear out environment as best is possible before executing
anything. especially PATH and IFS are set to minimal base defaults.
also use clearenv() if available and unsetenv()

2. remove gdb method as it's just too dangerous. run it as normal as
the user and if the kernel / distro dny that - then sorry. too bad.

Conflicts:
	data/etc/sysactions.conf.in
	src/bin/e_sys_main.c

configure.ac

@@ -74,6 +74,8 @@ EFL_CHECK_PATH_MAX
 
 AC_CHECK_FUNCS(setenv)
 AC_CHECK_FUNCS(unsetenv)
+AC_CHECK_FUNCS(clearenv)
+AC_CHECK_HEADERS([features.h])
 
 efl_version="1.7.9"
 AC_SUBST(efl_version)

data/etc/sysactions.conf.in

@@ -50,7 +50,6 @@ action:   hibernate @HIBERNATE@
 action:   /bin/mount /bin/mount
 action:   /bin/umount /bin/umount
 action:   /usr/bin/eject /usr/bin/eject
-action:   gdb       gdb
 
 # on FreeBSD use this instead of the above.
 #action suspend  /usr/sbin/zzz 

src/bin/e_start_main.c

@@ -517,8 +517,7 @@ main(int argc, char **argv)
                               {
                                  /* call e_sys gdb */
                                  snprintf(buffer, 4096,
-                                          "%s/enlightenment/utils/enlightenment_sys gdb %i %s/.e-crashdump.txt",
-                                          eina_prefix_lib_get(pfx),
+                                          "gdb %i %s/.e-crashdump.txt",
                                           child,
                                           home);
                                  r = system(buffer);

src/bin/e_sys_main.c

@@ -1,5 +1,11 @@
 #include "config.h"
 
+#define __USE_MISC
+#define _SVID_SOURCE
+#ifdef HAVE_FEATURES_H
+# include <features.h>
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -51,7 +57,6 @@ main(int argc,
    const char *act;
 #endif
    gid_t gid, gl[65536], egid;
-   int pid = 0;
 
    for (i = 1; i < argc; i++)
      {
@@ -73,21 +78,6 @@ main(int argc,
              test = 1;
              action = argv[2];
           }
-   else if (!strcmp(argv[1], "gdb"))
-     {
-        if (argc != 4) exit(1);
-        char *end = NULL;
-
-        action = argv[1];
-        pid = strtoul(argv[2], &end, 10);
-        if (end == NULL || *end != '\0')
-          {
-             printf("Invalid pid for '%s'.\n", argv[3]);
-             exit(0);
-          }
-
-        output = argv[3];
-     }
 #ifdef HAVE_EEZE_MOUNT
         else
           {
@@ -154,31 +144,28 @@ main(int argc,
         exit(20);
      }
 
-   if (!strcmp(action, "gdb"))
-     {
-        char buffer[4096];
-        int r;
+   /* sanitize environment */
+#ifdef HAVE_UNSETENV
+# define NOENV(x) unsetenv(x)
+#else
+# define NOENV(x)
+#endif
+   NOENV("IFS");
+   NOENV("LD_PRELOAD");
+   NOENV("PYTHONPATH");
+   NOENV("LD_LIBRARY_PATH");
+#ifdef HAVE_CLEARENV
+     clearenv();
+#endif
+   /* set path and ifs to minimal defaults */
+   putenv("PATH=/bin:/usr/bin");
+   putenv("IFS= \t\n");
 
-	snprintf(buffer, 4096,
-                 "%s --pid=%i "
-                 "-batch "
-                 "-ex 'set logging file %s' "
-                 "-ex 'set logging on' "
-                 "-ex 'thread apply all backtrace full' "
-                 "-ex detach > /dev/null 2>&1 < /dev/zero",
-                 cmd,
-		 pid,
-		 output ?: "e-output.txt");
-
-        r = system(buffer);
-
-        exit(WEXITSTATUS(r));
-     }
    if ((!test)
 #ifdef HAVE_EEZE_MOUNT
     && (!mnt)
 #endif
-      )
+       )
      return system(cmd);
 #ifdef HAVE_EEZE_MOUNT
    if (mnt)