DEBIAN-CVE-2026-99233: High severity debian/linux vulnerability

In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Verify eventcall identity when updating synthevent refcount In eventhisttriggerparse() and histunregall(), the histogram registration and unregistration paths look up findsynthevent() using traceeventname(file->eventcall) and adjust se->ref if a match is found. Because findsynthevent() only compares the event basename, registering or removing a histogram on a non-synthetic trace event whose basename matches a synthetic event erroneously modifies the synthetic event's reference count. If a histogram is registered on the non-synthetic event before the synthetic event is created and removed afterwards, se->ref is decremented without a matching increment, allowing the synthetic event to be freed while an active histogram action still holds a pointer to it. Introduce findsyntheventcall() to verify that &se->call matches file->eventcall before adjusting se->ref.