# DF-0514 — Low-severity source-confirmation

**Verdict:** NOT_REPRODUCED

**Impact:** none   **Confidence:** certain

**Kernel ref:** `sys/net/ipfw/ip_fw2.c:3323`

## Mechanism / why
FALSE POSITIVE: the TCP-match path does PULLUP_TO(hlen + sizeof(struct tcphdr)) (full 20-byte header) before any th_flags/th_ack/th_win reads (ip_fw2.c:3323,3932); th_win/th_sum/th_urp ARE covered. The cited :629/:773 line numbers do not match current master.

## Recommended fix
No code change needed: false positive (full tcphdr pulled before th_* reads).

## Phase 8 (combined build)
All 80 Low-severity fixes were batched into one patch (`../_batch_low/combined_all.patch`) and applied to the in-guest `/usr/src`. A single `make -j6 nativekernel KERNCONF=X86_64_GENERIC` completed rc=0 with **0 errors under -Werror** (`../_batch_low/fix_build.log`). The GENERIC-compiled fixes (net/radix, netinet, netinet6, wlan, wlan_ccmp, wlan_wep, altq, if_mib) are build-validated; module-only/netgraph/ipfw3/netsmb/vlan/sl/disc fixes apply cleanly to source (those subsystems are optional, not compiled into GENERIC).