CVE-2026-64270

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

Input: mms114 - reject an oversized device packet size

mms114_interrupt() reads a packet of touch data from the device into a

fixed-size on-stack buffer

struct mms114_touch touch[MMS114_MAX_TOUCH];

which holds MMS114_MAX_TOUCH (10) events of MMS114_EVENT_SIZE (8) bytes,

i.e. 80 bytes. The length of the I2C read into it is taken verbatim from

the device:

packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);

if (packet_size <= 0)

goto out;

...

error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,

(u8 *)touch);

packet_size is a single device register byte (0x0F) and the only check

is the lower bound packet_size <= 0; it is never bounded against the

size of touch[]. A malfunctioning, malicious or counterfeit controller

(or an attacker tampering with the I2C bus) can report a packet_size of

up to 255, so __mms114_read_reg() writes up to 175 bytes past the end of

touch[] on the IRQ-thread stack: a stack out-of-bounds write that can

overwrite the stack canary, saved registers and the return address.

A well-formed device never reports more than the buffer holds, so reject

an oversized packet and drop the report, consistent with the handler's

other error paths, rather than reading past the buffer.