forked from unom/punktfunk
enricobuehlerandClaude Opus 4.8
b22d0da75b
Three defects from the pf-encode sweep, each adjudicated against source. - Vulkan Video never received fecbec2d's taint sweep (it was carved out one commit later). `pick_recovery_slot` accepts any resident slot whose wire is below the CURRENT loss start, but "resident and older than this loss" is not "the client decoded it": after an earlier loss [a,b] recovered at wire r, everything in [a, r-1] is undecodable at the client — the lost frames plus every frame that predicted through the gap — and those wires stay eligible until the 8-slot ring rolls them out. A later loss could therefore anchor on one and ship it tagged `recovery_anchor`, which is the client's definitive re-anchor signal (punktfunk-core/src/reanchor.rs): the host lifts the client's post-loss freeze onto a picture built from a reference it never had. Swept before anchor selection, matching AMF/QSV. `slot_wire` is blanked and `slot_poc` deliberately is NOT: `slot_poc` feeds `build_h265_rps_s0`, which must keep naming every physically-resident DPB picture or a conforming decoder evicts them and the anchor then references a picture the client already dropped. - QSV's sweep was incomplete, and in its MODAL case. `ltr_slots` mirrors the hardware DPB, but nulling an entry issues no VPL call — the frame stays marked long-term until that LongTermIdx is re-marked or an IDR flushes it (amf.rs states this verbatim). The rejection loop iterates the post-sweep mirror and only rejects `Some` slots, so it silently skipped the single entry the sweep exists to distrust, leaving the recovery frame free to predict from it. With NUM_LTR_SLOTS=2 the "exactly one slot swept" case is the common one, and the two existing tests cover only the both-survive and both-swept cases. Taint is now recorded in `ltr_tainted` with the FrameOrder left in place, so anchor selection and the queued-force guard skip it while the rejection list still names it. - `read_slot` built a slice from the driver-reported (offset, bytes-written) encode feedback with no validation against `bs_size`, so a driver reporting a range outside the bitstream buffer produced an out-of-bounds read shipped straight onto the wire. Checked in u64 (so the add cannot wrap) before `map_memory`, so the error path has no unmap to unwind. Adds `taint_sweep_excludes_slots_from_an_earlier_loss` covering the two-loss case the existing single-loss test does not reach. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>