# DF-4496 VERDICT

**Status: untested** (kernel-level) — model-confirmed. **Impact: none on
this guest** (hardware-gated). **Confidence: certain** (source).

## Reproduced?

At the *kernel* level: no — and it cannot be on this guest. `env.txt`
records 0 AMD/ATI PCI devices; the dce100 pool-construction path only runs
during `amdgpu` bind on a DCE10 ASIC. Same verification ceiling as the
accepted family twins DF-4318 (dce80), DF-4353 (dce110), DF-4376 (dce112).

What *was* verified:

1. **Line-accurate source trace.** `dce100_create_resource_pool`
   (`dce100_resource.c:1056-1071`): kzalloc at :1060-1061, success return
   at :1066-1067, failure arm :1069-1070 returns NULL with **no
   `kfree(pool)`**. `construct()`'s error arm `res_create_fail`
   (:1050-1053) runs `destruct(pool)` (:678-745), which frees only the
   sub-objects (opps/transforms/ipps/mis/tgs :682-701, engines/i2cs
   :703-714, stream_encs :716-719, clock sources :721-727, audios
   :729-732, dccg/abm/dmcu/irqs :734-744) — never the shell. The only
   `kfree(dce110_pool)` is in `dce100_destroy_resource_pool` (:838-845),
   reachable only through a pool that was returned successfully. The
   caller `dc_create_resource_pool` (`core/dc_resource.c:125-128`)
   receives NULL and cannot free an allocation it never saw.
2. **Guest-side control-flow model** (`df4496.c`, guest `cc 8.3`, full
   output in `run.log`/`run.2.log`): exact control-flow copy of
   :1056-1071 with allocation accounting — failure path ends with
   `live_allocs=1` (the orphaned shell) while all children were reclaimed
   by the modeled `destruct()`; success path drops to 0 after destroy,
   proving the ownership accounting is faithful. Two independent runs
   identical.

## Exploit chain

None — one-shot, ~2 KB (`sizeof(struct dce110_resource_pool)`,
`dce110_resource.h:37-39`) kernel-heap leak per failed `amdgpu` bind on a
DCE10/Tonga ASIC (any sub-object allocation failure at probe, e.g. OOM or
a failing `resource_construct`). Not reachable by unprivileged users;
severity Low, family precedent DF-4318/4353/4376.

## Fix validation

`fix.diff` adds `kfree(pool);` before the failure return — identical to
the accepted DF-4318 fix shape. `git apply --check` passes against the
read-only tree. Fix not kernel-testable on this guest (no AMD device):
`fix_status: not_testable`.

## Fix status (batch validation)
Applied with the 36 sibling fix.diffs of this batch in findings/poc/_batch41/all_fixes.patch; single in-guest `make -j6 nativekernel KERNCONF=X86_64_GENERIC` completed RC=0 with zero errors under -Werror (full log: findings/poc/_batch41/fix_build8.log). Behavior A/B intentionally skipped for this Info-tier item.