diff options
Diffstat (limited to 'security/selinux/ss/ebitmap.c')
| -rw-r--r-- | security/selinux/ss/ebitmap.c | 20 |
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; |