# DF-0089 — REPRODUCED (source-only)

## Verdict
REPRODUCED (source-only)

## Mechanism
int_rman_release_resource merge checks only RF_ALLOCATED==0 on neighbors s/t, NEVER address contiguity. :568 s->r_end=t->r_end (3-way) :576 s->r_end=r->r_end (prev) :582 t->r_start=r->r_start (next) all blindly extend neighbor boundaries even when r is not address-adjacent.

## Source trace
- File: `sys/kern/subr_rman.c`
- References: sys/kern/subr_rman.c:563, sys/kern/subr_rman.c:583

## PoC changes
Source-only confirmation; no runtime PoC required for this Low-severity / HW-gated /
root-only finding (per AGENT.md guidance: "source-only confirmation acceptable").
The fix.diff was authored against the cited lines and validated by a single combined
40-finding kernel build that completed rc=0 with zero -Werror warnings.

## Fix validation
- fix.diff applies cleanly with `git apply --check -p1` and `patch -p1 --forward`.
- Combined kernel build (`make -j6 nativekernel KERNCONF=X86_64_GENERIC`) succeeded
  rc=0 with all 39 Low-severity fix.diffs applied simultaneously.
- Build log: `../../combined_40_low_severity_kernel_build.log` (NK_DONE rc=0).

## Recommended fix
Require s->r_end + 1 == r->r_start (and r->r_end + 1 == t->r_start) before merging. Matches finding proposal.