VYPR
← All advisories
Unrated severityNVD Advisory· Published May 22, 2024· Updated May 4, 2025

comedi: vmk80xx: fix transfer-buffer overflows

CVE-2021-47475

Description

In the Linux kernel, the following vulnerability has been resolved:

comedi: vmk80xx: fix transfer-buffer overflows

The driver uses endpoint-sized USB transfer buffers but up until recently had no sanity checks on the sizes.

Commit e1f13c879a7c ("staging: comedi: check validity of wMaxPacketSize of usb endpoints found") inadvertently fixed NULL-pointer dereferences when accessing the transfer buffers in case a malicious device has a zero wMaxPacketSize.

Make sure to allocate buffers large enough to handle also the other accesses that are done without a size check (e.g. byte 18 in vmk80xx_cnt_insn_read() for the VMK8061_MODEL) to avoid writing beyond the buffers, for example, when doing descriptor fuzzing.

The original driver was for a low-speed device with 8-byte buffers. Support was later added for a device that uses bulk transfers and is presumably a full-speed device with a maximum 64-byte wMaxPacketSize.

Affected products

100

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

9

News mentions

0

No linked articles in our index yet.