[PATCH] audit: fix broken class-based syscall audit

The sanity check in audit_match_class() is wrong.  We are able to audit
2048 syscalls but in audit_match_class() we were accidentally using
sizeof(_u32) instead of number of bits in _u32 when deciding how many
syscalls were valid.  On ia64 in particular we were hitting syscall
numbers over the (wrong) limit of 256.  Fixing the audit_match_class
check takes care of the problem.

Signed-off-by: Klaus Weidner <klaus@atsec.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

kernel/auditfilter.c

@@ -304,7 +304,7 @@ int __init audit_register_class(int class, unsigned *list)
 
 int audit_match_class(int class, unsigned syscall)
 {
-	if (unlikely(syscall >= AUDIT_BITMASK_SIZE * sizeof(__u32)))
+	if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
 		return 0;
 	if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
 		return 0;