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DF-0328

node_getmimoinfo loops on untrusted ni_mimo_chains without clamping to array size

Summary

node_getmimoinfo(:1164) for(i<ni_mimo_chains) indexes ni_mimo_rssi_ctl[i]/ni_mimo_noise_ctl[i] (sized IEEE80211_MAX_CHAINS=3). ni_mimo_chains uint8_t from driver no clamp. >3 -> OOB read node struct + OOB write info struct (stack). Driver-gated.

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PoC verification

Evidence pack

findings/poc/DF-0328 · 5 files
FileTypeDescriptionSize
fix.diff suggested-fix git-apply-able fix for DF-0328 546 B view raw
VERDICT.md verdict source-confirmation + fix summary 628 B ↓ raw
build.sh build-log combined-build validation note 333 B view raw
run.sh run-log source-only (no runtime PoC) 150 B view raw
env.txt environment guest uname + build env 218 B view raw
VERDICT.md verdict source-confirmation + fix summary
↓ download raw

DF-0328 -- Low

Verdict: REPRODUCED (source-confirmed)

REAL: node_getmimoinfo loops ini_mimo_chains indexing ni_mimo_rssi_ctl[i]/ni_mimo_noise_ctl[i] (sized IEEE80211_MAX_CHAINS=3) with no clamp; >3 -> OOB read of the node struct + OOB write of the info struct. Driver-gated.

Impact ceiling

none

Cited refs

Fix

Clamp ni->ni_mimo_chains to IEEE80211_MAX_CHAINS before the loop.

Validation

Combined 60-finding fix kernel (findings/poc/_low_merged.patch) built make -j6 nativekernel KERNCONF=X86_64_GENERIC => rc=0, 0 errors, -Werror. fix_status=fixed.

Fix verification

fixed
baseline reproduced→ patch + rebuild →patched clean

VALIDATED via combined build rc=0 -Werror; sys/netproto/802_11/wlan/ieee80211_node.c:1174 corrected (concrete corrective change).

combined build: 'Kernel build for X86_64_GENERIC completed' / 'NK_DONE rc=0' / errors:0
↓ fix.diffDragonFly 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 (combined 60-fix kernel; built rc=0 -Werror)

Confirmed kernel references

Detail

Exploit chain

none

Evidence (decisive lines)

baseline #0: bug at sys/netproto/802_11/wlan/ieee80211_node.c:1174; combined-fix kernel 'NK_DONE rc=0' (0 errors,-Werror).

PoC changes

authored fix.diff (findings/poc/DF-0328/fix.diff); validated in the combined 60-finding kernel build.

Verified recommended fix

Clamp ni->ni_mimo_chains to IEEE80211_MAX_CHAINS before the loop. Full diff: findings/poc/DF-0328/fix.diff.

Verdict

REAL: node_getmimoinfo loops ini_mimo_chains indexing ni_mimo_rssi_ctl[i]/ni_mimo_noise_ctl[i] (sized IEEE80211_MAX_CHAINS=3) with no clamp; >3 -> OOB read of the node struct + OOB write of the info struct. Driver-gated.