CVE-2026-43388

/// Technical description

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

mm/damon/core: clear walk_control on inactive context in damos_walk()

damos_walk() sets ctx->walk_control to the caller-provided control

structure before checking whether the context is running. If the context

is inactive (damon_is_running() returns false), the function returns

-EINVAL without clearing ctx->walk_control. This leaves a dangling

pointer to a stack-allocated structure that will be freed when the caller

returns.

This is structurally identical to the bug fixed in commit f9132fbc2e83

("mm/damon/core: remove call_control in inactive contexts") for

damon_call(), which had the same pattern of linking a control object and

returning an error without unlinking it.

The dangling walk_control pointer can cause:

1. Use-after-free if the context is later started and kdamond

   dereferences ctx->walk_control (e.g., in damos_walk_cancel()

   which writes to control->canceled and calls complete())

2. Permanent -EBUS

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. 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.

/// References