struct bsx64 *pbsx = &ppbr->bsx;
unsigned int i;
- /* Fill exfat BIOS paramemter block */
+ /* Fill exfat BIOS parameter block */
pbpb->jmp_boot[0] = 0xeb;
pbpb->jmp_boot[1] = 0x76;
pbpb->jmp_boot[2] = 0x90;
memcpy(pbpb->oem_name, "EXFAT ", 8);
memset(pbpb->res_zero, 0, 53);
- /* Fill exfat extend BIOS paramemter block */
+ /* Fill exfat extend BIOS parameter block */
pbsx->vol_offset = cpu_to_le64(bd->offset / bd->sector_size);
pbsx->vol_length = cpu_to_le64(bd->size / bd->sector_size);
pbsx->fat_offset = cpu_to_le32(finfo.fat_byte_off / bd->sector_size);
unsigned long long offset)
{
int nbyte;
+ off_t fat_entry_offset = finfo.fat_byte_off + (offset * sizeof(__le32));
- lseek(fd, finfo.fat_byte_off + (offset * sizeof(__le32)), SEEK_SET);
- nbyte = write(fd, (__u8 *) &clu, sizeof(__le32));
+ nbyte = pwrite(fd, (__u8 *) &clu, sizeof(__le32), fat_entry_offset);
if (nbyte != sizeof(int)) {
exfat_err("write failed, offset : %llu, clu : %x\n",
offset, clu);
char *bitmap;
unsigned int i, nbytes;
- bitmap = calloc(finfo.bitmap_byte_len, sizeof(*bitmap));
+ bitmap = calloc(round_up(finfo.bitmap_byte_len, sizeof(bitmap_t)),
+ sizeof(*bitmap));
if (!bitmap)
return -1;
- for (i = 0; i < finfo.used_clu_cnt - EXFAT_FIRST_CLUSTER; i++)
- exfat_set_bit(bd, bitmap, i);
+ for (i = EXFAT_FIRST_CLUSTER; i < finfo.used_clu_cnt; i++)
+ exfat_bitmap_set(bitmap, i);
- lseek(bd->dev_fd, finfo.bitmap_byte_off, SEEK_SET);
- nbytes = write(bd->dev_fd, bitmap, finfo.bitmap_byte_len);
+ nbytes = pwrite(bd->dev_fd, bitmap, finfo.bitmap_byte_len, finfo.bitmap_byte_off);
if (nbytes != finfo.bitmap_byte_len) {
exfat_err("write failed, nbytes : %d, bitmap_len : %d\n",
nbytes, finfo.bitmap_byte_len);
static int exfat_create_root_dir(struct exfat_blk_dev *bd,
struct exfat_user_input *ui)
{
- struct exfat_dentry ed[3];
+ struct exfat_dentry ed[3] = {0};
int dentries_len = sizeof(struct exfat_dentry) * 3;
int nbytes;
ed[2].upcase_start_clu = cpu_to_le32(finfo.ut_start_clu);
ed[2].upcase_size = cpu_to_le64(EXFAT_UPCASE_TABLE_SIZE);
- lseek(bd->dev_fd, finfo.root_byte_off, SEEK_SET);
- nbytes = write(bd->dev_fd, ed, dentries_len);
+ nbytes = pwrite(bd->dev_fd, ed, dentries_len, finfo.root_byte_off);
if (nbytes != dentries_len) {
exfat_err("write failed, nbytes : %d, dentries_len : %d\n",
nbytes, dentries_len);
unsigned long long total_clu_cnt;
int clu_len;
+ if (ui->cluster_size < bd->sector_size) {
+ exfat_err("cluster size (%u bytes) is smaller than sector size (%u bytes)\n",
+ ui->cluster_size, bd->sector_size);
+ return -1;
+ }
if (ui->boundary_align < bd->sector_size) {
exfat_err("boundary alignment is too small (min %d)\n",
bd->sector_size);
}
finfo.fat_byte_off = round_up(bd->offset + 24 * bd->sector_size,
ui->boundary_align) - bd->offset;
- finfo.fat_byte_len = round_up((bd->num_clusters * sizeof(int)),
- ui->cluster_size);
+ /* Prevent integer overflow when computing the FAT length */
+ if (bd->num_clusters > UINT32_MAX / 4) {
+ exfat_err("cluster size (%u bytes) is too small\n", ui->cluster_size);
+ return -1;
+ }
+ finfo.fat_byte_len = round_up((bd->num_clusters * 4), ui->cluster_size);
finfo.clu_byte_off = round_up(bd->offset + finfo.fat_byte_off +
finfo.fat_byte_len, ui->boundary_align) - bd->offset;
if (bd->size <= finfo.clu_byte_off) {