diff options
| -rw-r--r-- | hw/scsi-disk.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c index 3959603b0f..d621852857 100644 --- a/hw/scsi-disk.c +++ b/hw/scsi-disk.c @@ -1456,9 +1456,13 @@ static inline bool check_lba_range(SCSIDiskState *s, * The first line tests that no overflow happens when computing the last * sector. The second line tests that the last accessed sector is in * range. + * + * Careful, the computations should not underflow for nb_sectors == 0, + * and a 0-block read to the first LBA beyond the end of device is + * valid. */ return (sector_num <= sector_num + nb_sectors && - sector_num + nb_sectors - 1 <= s->qdev.max_lba); + sector_num + nb_sectors <= s->qdev.max_lba + 1); } typedef struct UnmapCBData { |