diff options
Diffstat (limited to 'security/landlock/audit.c')
| -rw-r--r-- | security/landlock/audit.c | 81 |
1 files changed, 25 insertions, 56 deletions
diff --git a/security/landlock/audit.c b/security/landlock/audit.c index e899995f1fd5..60ff217ab95b 100644 --- a/security/landlock/audit.c +++ b/security/landlock/audit.c @@ -180,38 +180,21 @@ static void test_get_hierarchy(struct kunit *const test) #endif /* CONFIG_SECURITY_LANDLOCK_KUNIT_TEST */ +/* Get the youngest layer that denied the access_request. */ static size_t get_denied_layer(const struct landlock_ruleset *const domain, access_mask_t *const access_request, - const layer_mask_t (*const layer_masks)[], - const size_t layer_masks_size) + const struct layer_access_masks *masks) { - const unsigned long access_req = *access_request; - unsigned long access_bit; - access_mask_t missing = 0; - long youngest_layer = -1; - - for_each_set_bit(access_bit, &access_req, layer_masks_size) { - const layer_mask_t mask = (*layer_masks)[access_bit]; - long layer; - - if (!mask) - continue; - - /* __fls(1) == 0 */ - layer = __fls(mask); - if (layer > youngest_layer) { - youngest_layer = layer; - missing = BIT(access_bit); - } else if (layer == youngest_layer) { - missing |= BIT(access_bit); + for (ssize_t i = ARRAY_SIZE(masks->access) - 1; i >= 0; i--) { + if (masks->access[i] & *access_request) { + *access_request &= masks->access[i]; + return i; } } - *access_request = missing; - if (youngest_layer == -1) - return domain->num_layers - 1; - - return youngest_layer; + /* Not found - fall back to default values */ + *access_request = 0; + return domain->num_layers - 1; } #ifdef CONFIG_SECURITY_LANDLOCK_KUNIT_TEST @@ -221,50 +204,39 @@ static void test_get_denied_layer(struct kunit *const test) const struct landlock_ruleset dom = { .num_layers = 5, }; - const layer_mask_t layer_masks[LANDLOCK_NUM_ACCESS_FS] = { - [BIT_INDEX(LANDLOCK_ACCESS_FS_EXECUTE)] = BIT(0), - [BIT_INDEX(LANDLOCK_ACCESS_FS_READ_FILE)] = BIT(1), - [BIT_INDEX(LANDLOCK_ACCESS_FS_READ_DIR)] = BIT(1) | BIT(0), - [BIT_INDEX(LANDLOCK_ACCESS_FS_REMOVE_DIR)] = BIT(2), + const struct layer_access_masks masks = { + .access[0] = LANDLOCK_ACCESS_FS_EXECUTE | + LANDLOCK_ACCESS_FS_READ_DIR, + .access[1] = LANDLOCK_ACCESS_FS_READ_FILE | + LANDLOCK_ACCESS_FS_READ_DIR, + .access[2] = LANDLOCK_ACCESS_FS_REMOVE_DIR, }; access_mask_t access; access = LANDLOCK_ACCESS_FS_EXECUTE; - KUNIT_EXPECT_EQ(test, 0, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 0, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, LANDLOCK_ACCESS_FS_EXECUTE); access = LANDLOCK_ACCESS_FS_READ_FILE; - KUNIT_EXPECT_EQ(test, 1, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 1, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, LANDLOCK_ACCESS_FS_READ_FILE); access = LANDLOCK_ACCESS_FS_READ_DIR; - KUNIT_EXPECT_EQ(test, 1, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 1, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, LANDLOCK_ACCESS_FS_READ_DIR); access = LANDLOCK_ACCESS_FS_READ_FILE | LANDLOCK_ACCESS_FS_READ_DIR; - KUNIT_EXPECT_EQ(test, 1, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 1, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, LANDLOCK_ACCESS_FS_READ_FILE | LANDLOCK_ACCESS_FS_READ_DIR); access = LANDLOCK_ACCESS_FS_EXECUTE | LANDLOCK_ACCESS_FS_READ_DIR; - KUNIT_EXPECT_EQ(test, 1, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 1, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, LANDLOCK_ACCESS_FS_READ_DIR); access = LANDLOCK_ACCESS_FS_WRITE_FILE; - KUNIT_EXPECT_EQ(test, 4, - get_denied_layer(&dom, &access, &layer_masks, - sizeof(layer_masks))); + KUNIT_EXPECT_EQ(test, 4, get_denied_layer(&dom, &access, &masks)); KUNIT_EXPECT_EQ(test, access, 0); } @@ -370,9 +342,6 @@ static bool is_valid_request(const struct landlock_request *const request) return false; } - if (WARN_ON_ONCE(!!request->layer_masks ^ !!request->layer_masks_size)) - return false; - if (request->deny_masks) { if (WARN_ON_ONCE(!request->all_existing_optional_access)) return false; @@ -406,12 +375,12 @@ void landlock_log_denial(const struct landlock_cred_security *const subject, if (missing) { /* Gets the nearest domain that denies the request. */ if (request->layer_masks) { - youngest_layer = get_denied_layer( - subject->domain, &missing, request->layer_masks, - request->layer_masks_size); + youngest_layer = get_denied_layer(subject->domain, + &missing, + request->layer_masks); } else { youngest_layer = get_layer_from_deny_masks( - &missing, request->all_existing_optional_access, + &missing, _LANDLOCK_ACCESS_FS_OPTIONAL, request->deny_masks); } youngest_denied = |