[apparmor] [PATCH] handle upstream AppArmor more gracefully

[Kees Cook]

When loading without the 2.4 compatibility patch, the parser needs the
following patch or it will explode when it can't find the "features" file.

Nominated for 2.5.1.


=== modified file 'parser/parser_main.c'
--- parser/parser_main.c	2010-09-14 19:45:34 +0000
+++ parser/parser_main.c	2010-09-15 00:57:04 +0000
@@ -934,6 +934,15 @@
 	get_match_string();
 	/* Get kernel features string */
 	get_flags_string(&flags_string, FLAGS_FILE);
+	/* Gracefully handle AppArmor kernel without compatibility patch */
+	if (!flags_string) {
+		PERROR("Cache read/write disabled: %s interface file missing. "
+			"(Kernel needs AppArmor 2.4 compatibility patch.)\n",
+			FLAGS_FILE);
+		write_cache = 0;
+		skip_read_cache = 1;
+		return;
+	}
 
 	/*
          * Deal with cache directory versioning:


-- 
Kees Cook
Ubuntu Security Team