Refine sepolicy-analyze -D / dup detection.

We were incorrectly reporting overlapping rules as duplicates.
Only report cases where an attribute-based rule is a superset
of type-based rule.  Also omit self rules as they are often due
to expansion of domain self rules by checkpolicy.

Change-Id: I27f33cdf9467be5fdb6ce148aa0006d407291833
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
This commit is contained in:
Stephen Smalley 2014-06-17 14:32:46 -04:00
parent b4adc62a57
commit 43b9cfd356

View file

@ -11,6 +11,7 @@
#include <sepol/policydb/services.h>
#include <sepol/policydb/expand.h>
#include <sepol/policydb/util.h>
#include <stdbool.h>
void usage(char *arg0)
{
@ -343,15 +344,23 @@ static int find_dups_helper(avtab_key_t * k, avtab_datum_t * d,
unsigned int i, j;
avtab_key_t avkey;
avtab_ptr_t node;
struct type_datum *stype, *ttype, *stype2, *ttype2;
bool attrib1, attrib2;
if (!(k->specified & AVTAB_ALLOWED))
return 0;
if (k->source_type == k->target_type)
return 0; /* self rule */
avkey.target_class = k->target_class;
avkey.specified = k->specified;
sattr = &policydb->type_attr_map[k->source_type - 1];
tattr = &policydb->type_attr_map[k->target_type - 1];
stype = policydb->type_val_to_struct[k->source_type - 1];
ttype = policydb->type_val_to_struct[k->target_type - 1];
attrib1 = stype->flavor || ttype->flavor;
ebitmap_for_each_bit(sattr, snode, i) {
if (!ebitmap_node_get_bit(snode, i))
continue;
@ -363,14 +372,26 @@ static int find_dups_helper(avtab_key_t * k, avtab_datum_t * d,
if (avkey.source_type == k->source_type &&
avkey.target_type == k->target_type)
continue;
if (avkey.source_type == avkey.target_type)
continue; /* self rule */
stype2 = policydb->type_val_to_struct[avkey.source_type - 1];
ttype2 = policydb->type_val_to_struct[avkey.target_type - 1];
attrib2 = stype2->flavor || ttype2->flavor;
if (attrib1 && attrib2)
continue; /* overlapping attribute-based rules */
for (node = avtab_search_node(&policydb->te_avtab, &avkey);
node != NULL;
node = avtab_search_node_next(node, avkey.specified)) {
if (node->datum.data & d->data) {
uint32_t perms = node->datum.data & d->data;
if ((attrib1 && perms == node->datum.data) ||
(attrib2 && perms == d->data)) {
/*
* The attribute-based rule is a superset of the
* non-attribute-based rule. This is a dup.
*/
printf("Duplicate allow rule found:\n");
display_allow(policydb, k, i, perms);
display_allow(policydb, &node->key, i, perms);
display_allow(policydb, k, i, d->data);
display_allow(policydb, &node->key, i, node->datum.data);
printf("\n");
}
}