CVE-2026-46294

Technical Description

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

dm: fix a buffer overflow in ioctl processing

Tony Asleson (using Claude) found a buffer overflow in dm-ioctl in the

function retrieve_status:

1. The code in retrieve_status checks that the output string fits into

the output buffer and writes the output string there

2. Then, the code aligns the "outptr" variable to the next 8-byte

boundary:

outptr = align_ptr(outptr);

3. The alignment doesn't check overflow, so outptr could point past the

buffer end

4. The "for" loop is iterated again, it executes:

remaining = len - (outptr - outbuf);

5. If "outptr" points past "outbuf + len", the arithmetics wraps around

and the variable "remaining" contains unusually high number

6. With "remaining" being high, the code writes more data past the end of

the buffer

Luckily, this bug has no security implications because:

1. Only root can issue device mapper ioctls

2. The commonly used libraries that communicate with

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References