CD-ROM: Add max blocks check.

The code does not support more than 2^32 - 2 blocks because of this expression: static_cast<uint32_t>(this->size_blocks + 1)

devices/storage/blockstoragedevice.cpp

@@ -25,9 +25,10 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 using namespace std;
 
-BlockStorageDevice::BlockStorageDevice(const uint32_t cache_blocks, const uint32_t block_size) {
+BlockStorageDevice::BlockStorageDevice(const uint32_t cache_blocks, const uint32_t block_size, const uint64_t max_blocks) {
     this->block_size = block_size;
     this->cache_size = cache_blocks * this->block_size;
+    this->max_blocks = max_blocks;
 
     // allocate device cache and fill it with zeroes
     this->data_cache = std::unique_ptr<char[]>(new char[this->cache_size] ());
@@ -46,6 +47,9 @@ int BlockStorageDevice::set_host_file(std::string file_path) {
 
     this->size_bytes  = this->img_file.size();
     this->size_blocks = this->size_bytes / this->block_size;
+    if (this->size_blocks > this->max_blocks)
+        return -1;
+
     this->set_fpos(0);
 
     this->is_ready = true;

devices/storage/blockstoragedevice.h

@@ -32,7 +32,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 class BlockStorageDevice {
 public:
-    BlockStorageDevice(const uint32_t cache_blocks, const uint32_t block_size=512);
+    BlockStorageDevice(const uint32_t cache_blocks, const uint32_t block_size=512, const uint64_t max_blocks=0xffffffffffffffff);
     ~BlockStorageDevice();
 
     void set_block_size(const int blk_size) { this->block_size = blk_size; };
@@ -49,6 +49,7 @@ protected:
     ImgFile         img_file;
     uint64_t        size_bytes   = 0;   // image file size in bytes
     uint64_t        size_blocks  = 0;   // image file size in blocks
+    uint64_t        max_blocks   = 0;   // maximum number of blocks supported
     uint64_t        cur_fpos     = 0;   // current image file pointer position
     uint32_t        block_size   = 512; // physical block size
     uint32_t        cache_size   = 0;   // cache size

devices/storage/cdromdrive.cpp

@@ -30,7 +30,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include <cstring>
 #include <string>
 
-CdromDrive::CdromDrive() : BlockStorageDevice(31, 2048) {
+CdromDrive::CdromDrive() : BlockStorageDevice(31, 2048, 0xfffffffe) {
     this->is_writeable = false;
 }
 
@@ -133,7 +133,7 @@ uint32_t CdromDrive::request_sense(uint8_t *data_ptr, uint8_t sense_key,
 }
 
 uint32_t CdromDrive::report_capacity(uint8_t *data_ptr) {
-    WRITE_DWORD_BE_A(data_ptr, this->size_blocks);
+    WRITE_DWORD_BE_A(data_ptr, static_cast<uint32_t>(this->size_blocks));
     WRITE_DWORD_BE_A(&data_ptr[4], this->block_size);
     return 8;
 }