CVE-2021-47475

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.