ata: libata-sff: Ensure that we cannot write outside the allocated buffer

reveliofuzzing reported that a SCSI_IOCTL_SEND_COMMAND ioctl with out_len
set to 0xd42, SCSI command set to ATA_16 PASS-THROUGH, ATA command set to
ATA_NOP, and protocol set to ATA_PROT_PIO, can cause ata_pio_sector() to
write outside the allocated buffer, overwriting random memory.

While a ATA device is supposed to abort a ATA_NOP command, there does seem
to be a bug either in libata-sff or QEMU, where either this status is not
set, or the status is cleared before read by ata_sff_hsm_move().
Anyway, that is most likely a separate bug.

Looking at __atapi_pio_bytes(), it already has a safety check to ensure
that __atapi_pio_bytes() cannot write outside the allocated buffer.

Add a similar check to ata_pio_sector(), such that also ata_pio_sector()
cannot write outside the allocated buffer.

Cc: stable@vger.kernel.org
Reported-by: reveliofuzzing <reveliofuzzing@gmail.com>
Closes: https://lore.kernel.org/linux-ide/CA+-ZZ_jTgxh3bS7m+KX07_EWckSnW3N2adX3KV63y4g7M4CZ2A@mail.gmail.com/
Link: https://lore.kernel.org/r/20250127154303.15567-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>

0 files changed, 0 insertions, 0 deletions