web commit by HenrikBrixAndersen: ikiwiki-mass-rebuild fails to drop privileges and execute ikiwiki

doc/bugs/ikiwiki-mass-rebuild_fails_to_drop_privileges_and_execute_ikiwiki.mdwn

@@ -0,0 +1,24 @@
+The ikiwiki-mass-rebuild utility fails to drop privileges and fails to execute ikiwiki on FreeBSD.
+
+The solution is to set the effective UID after setting the real UID, and to set $PATH in the environment before calling exec().
+
+Proposed patch:
+
+    --- ikiwiki-mass-rebuild.orig	2007-08-15 22:21:59.000000000 +0200
+    +++ ikiwiki-mass-rebuild	2007-10-25 13:04:10.000000000 +0200
+    @@ -22,13 +22,14 @@ sub processline {
+     		my ($uuid, $ugid) = (getpwnam($user))[2, 3];
+     		$)="$ugid $ugid";
+     		$(=$ugid;
+    -		$>=$uuid;
+     		$<=$uuid;
+    +		$>=$uuid;
+     		if ($< != $uuid || $> != $uuid || $( != $ugid || $) ne "$ugid $ugid") {
+     			die "failed to drop permissions to $user";
+     		}
+     		%ENV=();
+     		$ENV{HOME}=(getpwnam($user))[7];
+    +		$ENV{PATH}="/usr/bin:/usr/local/bin";
+     		exec("ikiwiki", "-setup", $setup, @ARGV);
+     		die "failed to run ikiwiki: $!";
+     	}