From db862ae72501a726cb70571395725a1938c6dcc1 Mon Sep 17 00:00:00 2001
From: szymonh <12231135+szymonh@users.noreply.github.com>
Date: Mon, 27 Sep 2021 21:11:44 +0200
Subject: [PATCH] Assure msc device block size is not zero

---
 src/class/msc/msc_device.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/class/msc/msc_device.c b/src/class/msc/msc_device.c
index 0fd592129..b65abe979 100644
--- a/src/class/msc/msc_device.c
+++ b/src/class/msc/msc_device.c
@@ -1,4 +1,4 @@
-/* 
+/*
  * The MIT License (MIT)
  *
  * Copyright (c) 2019 Ha Thach (tinyusb.org)
@@ -187,6 +187,11 @@ uint8_t rdwr10_validate_cmd(msc_cbw_t const* cbw)
       TU_LOG(MSC_DEBUG, "  SCSI case 4 Hi > Dn\r\n");
       status =  MSC_CSW_STATUS_FAILED;
     }
+    else if ( SCSI_CMD_READ_10 == cbw->command[0] && cbw->total_bytes / block_count == 0)
+    {
+      TU_LOG(MSC_DEBUG, " Computed block size 0\r\n");
+      status = MSC_CSW_STATUS_FAILED;
+    }
   }
 
   return status;