CVE-2026-97923

/// Technical description

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

tracing: Free histogram the var ref when its initialization fails

create_var_ref() allocates a VAR_REF hist_field and then calls

init_var_ref() to fill it in. When that fails the field is leaked.

commit 656fe2ba85e8 ("tracing: Use hist trigger's var_ref array to destroy

var_refs") made destroy_hist_field() return early for

HIST_FIELD_FL_VAR_REF, since var refs are freed by walking the trigger's

var_refs[] array instead. create_var_ref() adds the field to that array

only after init_var_ref() has succeeded, so on this path the field is in

neither place and nothing frees it. The call was correct when it was

written, before var refs were taken out of destroy_hist_field().

init_var_ref() cannot free it either. The caller owns the field, so

init_var_ref() undoes only its own string allocations and leaves the

field alone. Freeing it there would leave create_var_ref() passing freed

memory to destroy_hist_field(), which rea

/// 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