diff --git a/src/BlueSCSI_Toolbox.cpp b/src/BlueSCSI_Toolbox.cpp
index 2d537eca..dffae15c 100644
--- a/src/BlueSCSI_Toolbox.cpp
+++ b/src/BlueSCSI_Toolbox.cpp
@@ -251,12 +251,12 @@ void onGetFile10(char * dir_name) {
 void onSendFilePrep(char * dir_name)
 {
     char file_name[32+1];
-    memset(file_name, '\0', 32+1);
+
     scsiEnterPhase(DATA_OUT);
-    for (int i = 0; i < 32+1; ++i)
-    {
-        file_name[i] = scsiReadByte();
-    }
+    scsiRead(static_cast<uint8_t *>(static_cast<void *>(file_name)), 32+1, NULL);
+    file_name[32] = '\0';
+
+    debuglog("TOOLBOX OPEN FILE FOR WRITE: '", file_name, "'");
     SD.chdir(dir_name);
     gFile.open(file_name, FILE_WRITE);
     SD.chdir("/");
@@ -296,19 +296,22 @@ void onSendFile10(void)
     uint16_t bytes_sent = ((uint16_t)scsiDev.cdb[1] << 8)  | scsiDev.cdb[2];
     // 512 byte offset of where to put these bytes.
     uint32_t offset     = ((uint32_t)scsiDev.cdb[3] << 16) | ((uint32_t)scsiDev.cdb[4] << 8) | scsiDev.cdb[5];
-    uint16_t buf_size   = 512;
-    uint8_t buf[512];
+    const uint16_t BUFSIZE   = 512;
+    uint8_t buf[BUFSIZE];
 
-    // Check if last block of file, and not the only bock in file.
-    if(bytes_sent < buf_size)
+    // Do not allow buffer overrun
+    if (bytes_sent > BUFSIZE)
     {
-        buf_size = bytes_sent;
+        debuglog("TOOLBOX SEND FILE 10 ILLEGAL DATA SIZE");
+        gFile.close();
+        scsiDev.status = CHECK_CONDITION;
+        scsiDev.target->sense.code = ILLEGAL_REQUEST;
     }
 
     scsiEnterPhase(DATA_OUT);
     scsiRead(buf, bytes_sent, NULL);
     gFile.seekCur(offset * 512);
-    gFile.write(buf, buf_size);
+    gFile.write(buf, bytes_sent);
     if(gFile.getWriteError())
     {
         gFile.clearWriteError();