Merge pull request #2852 from GuavTek/recover_zero_length_desc

USBH: Recover from unexpected descriptor size

1 files changed, 7 insertions, 0 deletions

diff --git a/src/host/usbh.c b/src/host/usbh.c
index a9a692455..a2994cde7 100644
--- a/src/host/usbh.c
+++ b/src/host/usbh.c
@@ -1654,6 +1654,13 @@ static bool _parse_configuration_descriptor(uint8_t dev_addr, tusb_desc_configur
 
   // parse each interfaces
   while( p_desc < desc_end ) {
+    if ( 0 == tu_desc_len(p_desc) ) {
+      // A zero length descriptor indicates that the device is off spec (e.g. wrong wTotalLength).
+      // Parsed interfaces should still be usable
+      TU_LOG_USBH("Encountered a zero-length descriptor after %u bytes\r\n", (uint32_t)p_desc - (uint32_t)desc_cfg);
+      break;
+    }
+
     uint8_t assoc_itf_count = 1;
 
     // Class will always starts with Interface Association (if any) and then Interface descriptor