diff options
Diffstat (limited to 'extras/volume_id/libvolume_id/fat.c')
| -rw-r--r-- | extras/volume_id/libvolume_id/fat.c | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/extras/volume_id/libvolume_id/fat.c b/extras/volume_id/libvolume_id/fat.c index 26d0fe74ab..cea5b8cff2 100644 --- a/extras/volume_id/libvolume_id/fat.c +++ b/extras/volume_id/libvolume_id/fat.c @@ -161,48 +161,45 @@ int volume_id_probe_vfat(struct volume_id *id, uint64_t off) return -1; if (memcmp(vs->type.fat32.magic, "MSWIN", 5) == 0) - goto valid; + goto magic; if (memcmp(vs->type.fat32.magic, "FAT32 ", 8) == 0) - goto valid; + goto magic; if (memcmp(vs->type.fat.magic, "FAT16 ", 8) == 0) - goto valid; + goto magic; if (memcmp(vs->type.fat.magic, "MSDOS", 5) == 0) - goto valid; + goto magic; if (memcmp(vs->type.fat.magic, "FAT12 ", 8) == 0) - goto valid; + goto magic; - /* - * There are old floppies out there without a magic, so we check - * for well known values and guess if it's a fat volume - */ + /* some old floppies don't have a magic, so we expect the boot code to match */ /* boot jump address check */ if ((vs->boot_jump[0] != 0xeb || vs->boot_jump[2] != 0x90) && vs->boot_jump[0] != 0xe9) return -1; - /* heads check */ - if (vs->heads == 0) +magic: + /* reserverd sector count */ + if (!vs->reserved) return -1; - /* cluster size check*/ - if (vs->sectors_per_cluster == 0 || - (vs->sectors_per_cluster & (vs->sectors_per_cluster-1))) + /* fat count*/ + if (!vs->fats) return -1; /* media check */ if (vs->media < 0xf8 && vs->media != 0xf0) return -1; - /* fat count*/ - if (vs->fats != 2) + /* cluster size check*/ + if (vs->sectors_per_cluster == 0 || + (vs->sectors_per_cluster & (vs->sectors_per_cluster-1))) return -1; -valid: /* sector size check */ sector_size = le16_to_cpu(vs->sector_size); if (sector_size != 0x200 && sector_size != 0x400 && |