CVE-2025-21738 Information

Description

In the Linux kernel the following vulnerability has been resolved:

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.

Reference

https://git.kernel.org/stable/c/0a17a9944b8d89ef03946121241870ac53ddaf45 https://git.kernel.org/stable/c/0dd5aade301a10f4b329fa7454fdcc2518741902 https://git.kernel.org/stable/c/6e74e53b34b6dec5a50e1404e2680852ec6768d2 https://git.kernel.org/stable/c/a8f8cf87059ed1905c2a5c72f8b39a4f57b11b4c https://git.kernel.org/stable/c/d5e6e3000309359eae2a17117aa6e3c44897bf6c