Fix CVE-2016-1531

[exim.git] / src / src / exim.c

diff --git a/src/src/exim.c b/src/src/exim.c
index 8ab0456d83e74d3bf400c957b17bf57d7d862ec6..807f1ea87f4a8666de8ac21b67f28e6c002ba3b0 100644 (file)
--- a/src/src/exim.c
+++ b/src/src/exim.c
@@ -825,6 +825,12 @@ fprintf(f, "Support for:");
 #ifdef EXPERIMENTAL_PRDR
   fprintf(f, " Experimental_PRDR");
 #endif
+#ifdef EXPERIMENTAL_TPDA
+  fprintf(f, " Experimental_TPDA");
+#endif
+#ifdef EXPERIMENTAL_REDIS
+  fprintf(f, " Experimental_Redis");
+#endif
 fprintf(f, "\n");
 
 fprintf(f, "Lookups (built-in):");
@@ -3642,8 +3648,19 @@ init_lookup_list();
 is a failure. It leaves the configuration file open so that the subsequent
 configuration data for delivery can be read if needed. */
 
+/* To be safe: change the working directory to /. */
+if (Uchdir("/") < 0)
+  {
+    perror("exim: chdir `/': ");
+    exit(EXIT_FAILURE);
+  }
+
 readconf_main();
 
+if (cleanup_environment() == FALSE)
+  log_write(0, LOG_PANIC_DIE, "Can't cleanup environment");
+
+
 /* If an action on specific messages is requested, or if a daemon or queue
 runner is being started, we need to know if Exim was called by an admin user.
 This is the case if the real user is root or exim, or if the real group is
@@ -3789,7 +3806,7 @@ TMPDIR macro, if this macro is defined. */
 #ifdef TMPDIR
   {
   uschar **p;
-  for (p = USS environ; *p != NULL; p++)
+  if (environ) for (p = USS environ; *p != NULL; p++)
     {
     if (Ustrncmp(*p, "TMPDIR=", 7) == 0 &&
         Ustrcmp(*p+7, TMPDIR) != 0)
@@ -3829,10 +3846,10 @@ else
     uschar **new;
     uschar **newp;
     int count = 0;
-    while (*p++ != NULL) count++;
+    if (environ) while (*p++ != NULL) count++;
     if (envtz == NULL) count++;
     newp = new = malloc(sizeof(uschar *) * (count + 1));
-    for (p = USS environ; *p != NULL; p++)
+    if (environ) for (p = USS environ; *p != NULL; p++)
       {
       if (Ustrncmp(*p, "TZ=", 3) == 0) continue;
       *newp++ = *p;
@@ -4422,7 +4439,8 @@ if (list_options)
           (Ustrcmp(argv[i], "router") == 0 ||
            Ustrcmp(argv[i], "transport") == 0 ||
            Ustrcmp(argv[i], "authenticator") == 0 ||
-           Ustrcmp(argv[i], "macro") == 0))
+           Ustrcmp(argv[i], "macro") == 0 ||
+           Ustrcmp(argv[i], "environment") == 0))
         {
         readconf_print(argv[i+1], argv[i], flag_n);
         i++;