PTS test GATT/CL/GAD/BV-03-C published a service starting at handle 0xfffd and ending at 0xffff. This resets the next_handle to 0 in gatt_db_insert_service() instead of setting it to 0x10000. Other services are added later. This could end-up by a crash in db_hash_update() if not enough space has been allocated for hash.iov and some entries are overwritten. Next_handle can be replaced by a last_handle variable which will not loop over. This can be replaced by queue_peek_tail() and computing the value, but keeping last_handle will avoid this sort of lookup. --- src/shared/gatt-db.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/src/shared/gatt-db.c b/src/shared/gatt-db.c index 676f963ec..9559583d1 100644 --- a/src/shared/gatt-db.c +++ b/src/shared/gatt-db.c @@ -58,7 +58,7 @@ struct gatt_db { struct bt_crypto *crypto; uint8_t hash[16]; unsigned int hash_id; - uint16_t next_handle; + uint16_t last_handle; struct queue *services; struct queue *notify_list; @@ -255,7 +255,7 @@ struct gatt_db *gatt_db_new(void) db->crypto = bt_crypto_new(); db->services = queue_new(); db->notify_list = queue_new(); - db->next_handle = 0x0001; + db->last_handle = 0x0000; return gatt_db_ref(db); } @@ -356,14 +356,15 @@ static bool db_hash_update(void *user_data) db->hash_id = 0; - if (!db->next_handle) + if (gatt_db_isempty(db)) return false; - hash.iov = new0(struct iovec, db->next_handle); + hash.iov = new0(struct iovec, db->last_handle + 1); hash.i = 0; gatt_db_foreach_service(db, NULL, service_gen_hash_m, &hash); - bt_crypto_gatt_hash(db->crypto, hash.iov, db->next_handle, db->hash); + bt_crypto_gatt_hash(db->crypto, hash.iov, db->last_handle + 1, + db->hash); for (i = 0; i < hash.i; i++) free(hash.iov[i].iov_base); @@ -624,7 +625,7 @@ bool gatt_db_clear_range(struct gatt_db *db, uint16_t start_handle, done: if (gatt_db_isempty(db)) - db->next_handle = 0; + db->last_handle = 0; return true; } @@ -700,7 +701,7 @@ struct gatt_db_attribute *gatt_db_insert_service(struct gatt_db *db, return NULL; if (!handle) - handle = db->next_handle; + handle = db->last_handle + 1; if (num_handles < 1 || (handle + num_handles - 1) > UINT16_MAX) return NULL; @@ -747,8 +748,8 @@ struct gatt_db_attribute *gatt_db_insert_service(struct gatt_db *db, service->attributes[0]->handle = handle; service->num_handles = num_handles; - /* Fast-forward next_handle if the new service was added to the end */ - db->next_handle = MAX(handle + num_handles, db->next_handle); + /* Fast-forward last_handle if the new service was added to the end */ + db->last_handle = MAX(handle + num_handles - 1, db->last_handle); return service->attributes[0]; -- 2.34.1