summaryrefslogtreecommitdiffstats
path: root/security/selinux/ss/ebitmap.c
diff options
context:
space:
mode:
Diffstat (limited to 'security/selinux/ss/ebitmap.c')
-rw-r--r--security/selinux/ss/ebitmap.c20
1 files changed, 18 insertions, 2 deletions
diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c
index 30f119b1d1ec..820313a04d49 100644
--- a/security/selinux/ss/ebitmap.c
+++ b/security/selinux/ss/ebitmap.c
@@ -213,7 +213,12 @@ netlbl_import_failure:
}
#endif /* CONFIG_NETLABEL */
-int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2)
+/*
+ * Check to see if all the bits set in e2 are also set in e1. Optionally,
+ * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed
+ * last_e2bit.
+ */
+int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit)
{
struct ebitmap_node *n1, *n2;
int i;
@@ -223,14 +228,25 @@ int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2)
n1 = e1->node;
n2 = e2->node;
+
while (n1 && n2 && (n1->startbit <= n2->startbit)) {
if (n1->startbit < n2->startbit) {
n1 = n1->next;
continue;
}
- for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
+ for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i]; )
+ i--; /* Skip trailing NULL map entries */
+ if (last_e2bit && (i >= 0)) {
+ u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE +
+ __fls(n2->maps[i]);
+ if (lastsetbit > last_e2bit)
+ return 0;
+ }
+
+ while (i >= 0) {
if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
return 0;
+ i--;
}
n1 = n1->next;