Revert "ZSO Cleanup"

modules/iopcore/cdvdman/cdvdman.c

@@ -245,7 +245,7 @@ static int ProbeZSO(u8 *buffer)
     probed = 1;
     if (*(u32 *)buffer == ZSO_MAGIC) {
         // initialize ZSO
-        ziso_init((ZISO_header *)buffer);
+        ziso_init((ZISO_header *)buffer, *(u32 *)(buffer + sizeof(ZISO_header)));
         // initialize cache
         initCache();
         // redirect sector reader

modules/isofs/isofs.c

@@ -507,11 +507,15 @@ static int IsofsLseek(iop_file_t *f, int offset, int where)
 
 static int ProbeZISO(int fd)
 {
-    ZISO_header header;
+    struct
+    {
+        ZISO_header header;
+        u32 first_block;
+    } ziso_data;
     longLseek(fd, 0);
-    if (read(fd, &header, sizeof(header)) == sizeof(header) && header.magic == ZSO_MAGIC) {
+    if (read(fd, &ziso_data, sizeof(ziso_data)) == sizeof(ziso_data) && ziso_data.header.magic == ZSO_MAGIC) {
         // initialize ZSO
-        ziso_init(&header);
+        ziso_init(&ziso_data.header, ziso_data.first_block);
         // redirect cdEmuRead function
         cdEmuRead = &cdEmuReadCompressed;
         return 1;

modules/isofs/zso.c

@@ -11,20 +11,22 @@ int ziso_idx_start_block = -1;
 
 // header data that we need for the reader
 u32 ziso_align;
+u32 ziso_total_block;
 
 // block buffers
 u8 *ziso_tmp_buf = NULL;
 
-void ziso_init(ZISO_header *header)
+void ziso_init(ZISO_header *header, u32 first_block)
 {
     // read header information
     ziso_align = header->align;
-    // invalidate block offset cache
     ziso_idx_start_block = -1;
+    // calculate number of blocks without using uncompressed_size (avoid 64bit division)
+    ziso_total_block = ((((first_block & 0x7FFFFFFF) << ziso_align) - sizeof(ZISO_header)) / 4) - 1;
     // allocate memory
     if (ziso_tmp_buf == NULL) {
         ziso_tmp_buf = ziso_alloc(2048 + sizeof(u32) * ZISO_IDX_MAX_ENTRIES + 64);
-        if ((u32)ziso_tmp_buf & 63) // align 64 (is 64 needed? is 4 enough?)
+        if ((u32)ziso_tmp_buf & 63) // align 64
             ziso_tmp_buf = (void *)(((u32)ziso_tmp_buf & (~63)) + 64);
         if (ziso_tmp_buf) {
             ziso_idx_cache = (u32 *)(ziso_tmp_buf + 2048);
@@ -43,13 +45,16 @@ int ziso_read_sector(u8 *addr, u32 lsn, unsigned int count)
 
     u32 cur_block = lsn;
 
+    if (lsn >= ziso_total_block) {
+        return 0; // can't seek beyond file
+    }
+
     // refresh index table if needed
-    if (ziso_idx_start_block < 0 || lsn < ziso_idx_start_block || (lsn + count) - ziso_idx_start_block >= ZISO_IDX_MAX_ENTRIES - 1) {
+    if (ziso_idx_start_block < 0 || lsn < ziso_idx_start_block || lsn + count >= ziso_idx_start_block + ZISO_IDX_MAX_ENTRIES - 1) {
         read_raw_data((u8 *)ziso_idx_cache, ZISO_IDX_MAX_ENTRIES * sizeof(u32), lsn * 4 + sizeof(ZISO_header), 0);
         ziso_idx_start_block = lsn;
     }
 
-    // calculate total size of compressed data
     u32 o_start = (ziso_idx_cache[cur_block - ziso_idx_start_block] & 0x7FFFFFFF);
     u32 o_end = (ziso_idx_cache[cur_block + count - ziso_idx_start_block] & 0x7FFFFFFF);
     u32 compressed_size = (o_end - o_start) << ziso_align;
@@ -70,13 +75,16 @@ int ziso_read_sector(u8 *addr, u32 lsn, unsigned int count)
         b_size = (b_size & 0x7FFFFFFF);             // remove top bit
         b_size = (b_size - b_offset) << ziso_align; // calculate size of compressed block
 
+        // prevent reading more than a sector (eliminates padding if any)
+        int r = MIN(b_size, 2048);
+
         // check top bit to determine if block is compressed or raw
         if (topbit == 0) {                                                 // block is compressed
-            memcpy(ziso_tmp_buf, c_buff, b_size);                          // read compressed block into temp buffer
+            memcpy(ziso_tmp_buf, c_buff, r);                               // read compressed block into temp buffer
             LZ4_decompress_fast((char *)ziso_tmp_buf, (char *)addr, 2048); // decompress block
         } else {
             // move block to its correct position in the buffer
-            memcpy(addr, c_buff, 2048);
+            memcpy(addr, c_buff, r);
         }
 
         cur_block++;

modules/isofs/zso.h

@@ -33,11 +33,12 @@ extern int ziso_idx_start_block;
 
 // header data that we need for the reader
 extern u32 ziso_align;
+extern u32 ziso_total_block;
 
 // temp block buffer (2048 bytes)
 extern u8 *ziso_tmp_buf;
 
-void ziso_init(ZISO_header *header);
+void ziso_init(ZISO_header *header, u32 first_block);
 int ziso_read_sector(u8 *buf, u32 sector, unsigned int count);
 
 // This must be implemented by isofs/cdvdman/frontend

src/hddsupport.c

@@ -499,10 +499,9 @@ void hddLaunchGame(int id, config_set_t *configSet)
     if (*(u32 *)IOBuffer == ZSO_MAGIC) {
         probed_fd = 0;
         probed_lba = game->start_sector + OPL_HDD_MODE_PS2LOGO_OFFSET;
-        ziso_init((ZISO_header *)IOBuffer);
+        ziso_init((ZISO_header *)IOBuffer, *(u32 *)((u8 *)IOBuffer + sizeof(ZISO_header)));
         ziso_read_sector(IOBuffer, 16, 1);
         u32 maxLBA = *(u32 *)(IOBuffer + 80);
-        u32 ziso_total_block = ((ZISO_header *)IOBuffer)->total_bytes / 2048;
         if (maxLBA > 0 && maxLBA < ziso_total_block) {   // dual layer check
             settings->common.layer1_start = maxLBA - 16; // adjust second layer start
         }

src/supportbase.c

@@ -505,11 +505,15 @@ extern u8 IOBuffer[2048];
 
 static int ProbeZISO(int fd)
 {
-    ZISO_header header;
+    struct
+    {
+        ZISO_header header;
+        u32 first_block;
+    } ziso_data;
     lseek(fd, 0, SEEK_SET);
-    if (read(fd, &header, sizeof(header)) == sizeof(header) && header.magic == ZSO_MAGIC) {
+    if (read(fd, &ziso_data, sizeof(ziso_data)) == sizeof(ziso_data) && ziso_data.header.magic == ZSO_MAGIC) {
         // initialize ZSO
-        ziso_init(&header);
+        ziso_init(&ziso_data.header, ziso_data.first_block);
         // set ISO file descriptor for ZSO reader
         probed_fd = fd;
         probed_lba = 0;

src/util.c

@@ -538,7 +538,7 @@ int CheckPS2Logo(int fd, u32 lba)
 
     if (*(u32 *)logo == ZSO_MAGIC) {
         // initialize ZSO
-        ziso_init((ZISO_header *)logo);
+        ziso_init((ZISO_header *)logo, *(u32 *)((u8 *)logo + sizeof(ZISO_header)));
         probed_fd = fd;
         probed_lba = lba;
         // read ZISO data