diff options
| -rw-r--r-- | src/class/cdc/cdc_host.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/src/class/cdc/cdc_host.c b/src/class/cdc/cdc_host.c index d1cbc2924..f697c0e73 100644 --- a/src/class/cdc/cdc_host.c +++ b/src/class/cdc/cdc_host.c @@ -1024,6 +1024,8 @@ static uint16_t acm_open(uint8_t daddr, const tusb_desc_interface_t *itf_desc, u const uint8_t *p_desc = (const uint8_t *)itf_desc; const uint8_t *desc_end = p_desc + max_len; + TU_ASSERT(TU_DESC_VALIDATE(tu_desc_len(p_desc) <= max_len), 0); + cdch_interface_t *p_cdc = make_new_itf(daddr, itf_desc); TU_VERIFY(p_cdc, 0); p_cdc->serial_drid = SERIAL_DRIVER_ACM; @@ -1033,11 +1035,12 @@ static uint16_t acm_open(uint8_t daddr, const tusb_desc_interface_t *itf_desc, u // Communication Functional Descriptors // need the 3-byte header (bLength/bDescriptorType/bDescriptorSubType) in bounds before reading it, and a - // bLength >= 3 both keeps those reads valid and stops a zero-length descriptor from spinning the walk - while ((p_desc < desc_end) && TU_DESC_VALIDATE(p_desc + 3 <= desc_end) && - TUSB_DESC_CS_INTERFACE == tu_desc_type(p_desc) && TU_DESC_VALIDATE(tu_desc_len(p_desc) >= 3)) { + // fully contained bLength >= 3 both keeps those reads valid and stops a zero-length descriptor from spinning + while ((p_desc < desc_end) && TU_DESC_VALIDATE((size_t)(desc_end - p_desc) >= 3) && + TUSB_DESC_CS_INTERFACE == tu_desc_type(p_desc) && TU_DESC_VALIDATE(tu_desc_len(p_desc) >= 3) && + TU_DESC_VALIDATE(tu_desc_len(p_desc) <= (size_t)(desc_end - p_desc))) { if (CDC_FUNC_DESC_ABSTRACT_CONTROL_MANAGEMENT == cdc_functional_desc_typeof(p_desc) && - TU_DESC_VALIDATE(p_desc + sizeof(cdc_desc_func_acm_t) <= desc_end)) { + TU_DESC_VALIDATE(tu_desc_len(p_desc) >= sizeof(cdc_desc_func_acm_t))) { // save ACM bmCapabilities p_cdc->acm.capability = ((cdc_desc_func_acm_t const *) p_desc)->bmCapabilities; } @@ -1048,7 +1051,7 @@ static uint16_t acm_open(uint8_t daddr, const tusb_desc_interface_t *itf_desc, u // Open notification endpoint of control interface if any if (itf_desc->bNumEndpoints == 1) { // whole endpoint descriptor must fit: tuh_edpt_open reads the full struct regardless of bLength - TU_ASSERT(TU_DESC_VALIDATE(p_desc + sizeof(tusb_desc_endpoint_t) <= desc_end), 0); + TU_ASSERT(TU_DESC_VALIDATE((size_t)(desc_end - p_desc) >= sizeof(tusb_desc_endpoint_t)), 0); TU_ASSERT(TUSB_DESC_ENDPOINT == tu_desc_type(p_desc), 0); const tusb_desc_endpoint_t *desc_ep = (const tusb_desc_endpoint_t *)p_desc; TU_ASSERT(tuh_edpt_open(daddr, desc_ep), 0); @@ -1059,7 +1062,7 @@ static uint16_t acm_open(uint8_t daddr, const tusb_desc_interface_t *itf_desc, u } //------------- Data Interface (if any) -------------// - if (TU_DESC_VALIDATE(p_desc + sizeof(tusb_desc_interface_t) <= desc_end) && + if (TU_DESC_VALIDATE((size_t)(desc_end - p_desc) >= sizeof(tusb_desc_interface_t)) && TUSB_DESC_INTERFACE == tu_desc_type(p_desc)) { const tusb_desc_interface_t *data_itf = (const tusb_desc_interface_t *)p_desc; if (data_itf->bInterfaceClass == TUSB_CLASS_CDC_DATA) { @@ -1067,7 +1070,7 @@ static uint16_t acm_open(uint8_t daddr, const tusb_desc_interface_t *itf_desc, u // open_ep_stream_pair consumes exactly two endpoints; require that count and that both fit before reading them TU_ASSERT(TU_DESC_VALIDATE(data_itf->bNumEndpoints == 2), 0); - TU_ASSERT(TU_DESC_VALIDATE(p_desc + 2 * sizeof(tusb_desc_endpoint_t) <= desc_end), 0); + TU_ASSERT(TU_DESC_VALIDATE((size_t)(desc_end - p_desc) >= 2 * sizeof(tusb_desc_endpoint_t)), 0); TU_ASSERT(open_ep_stream_pair(p_cdc, (const tusb_desc_endpoint_t *)p_desc), 0); p_desc += 2 * sizeof(tusb_desc_endpoint_t); } |