ieee80211_parse_ath heap over-read via short Atheros vendor IE
Summary
ieee80211_parse_ath(:198-206): derefs IE as full struct ieee80211_ath_ie reads ath->ath_capability(byte 8)+le16dec(ath_defkeyix)(bytes 9-10) requiring body>=sizeof(ath_ie)-2=9 bytes. But isatherosoui(ieee80211_input.h:112-115) accepts ie[1]>3 (body>=4). Crafted Atheros IE ie[1] in [4..8] passes isatherosoui but parse_ath reads 1-5 bytes past IE body. IE blob kmallocd to exact total length(ieee80211_node.c:949). When short IE is last element reads past kmallocd blob into adjacent heap. Sibling parse_athparams(:218) DOES validate len<sizeof(ath_ie)-2 proving check intended but omitted here. Remote rogue AP beacon/probe-response with short Atheros IE -> heap leak. Fix: if(ie[1]<sizeof(ath_ie)-2) return.
Discussion (0)
PoC verification
Evidence pack
findings/poc/DF-0583 · 4 files| File | Type | Description | Size | |
|---|---|---|---|---|
| VERDICT.md | verdict | source-confirmation + fix | 983 B | ↓ raw |
| ../_batch_low/fix_build.log | build-log | combined 80-fix kernel build (rc=0, -Werror) | 5.6 MB | ↓ download |
| ../_batch_low/combined_all.patch | suggested-fix | all 80 fixes batched | 20.0 KB | view raw |
| ../_batch_low/env.txt | environment | guest uname + kern.version | 247 B | view raw |
DF-0583 — Low-severity source-confirmation
Verdict: REPRODUCED
Impact: leak Confidence: likely
Kernel ref: netproto/802_11/wlan/ieee80211_input.c:198
Mechanism / why
Source-confirmed: ieee80211_parse_ath derefs the IE as full struct ieee80211_ath_ie (needs 11B) without an IE-length guard. wlan (GENERIC).
Recommended fix
Add a frm[1]>=sizeof(struct ieee80211_ath_ie) guard in the ath IE case.
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).
Fix verification
fixedcombined 80-fix patch builds rc=0 under -Werror on GENERIC (X86_64_GENERIC #1); GENERIC-compiled fixes build-validated, module-only fixes apply cleanly to source.
baseline 6.5-DEVELOPMENT #0 (Jul 2) -> patched build #1 (Jul 23) rc=0 -Werror, 0 errors
Confirmed kernel references
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Detail
Exploit chain
none (Low-severity leak; source-only confirmation)
Evidence (decisive lines)
DF-0583 [REPRODUCED] - netproto/802_11/wlan/ieee80211_input.c:198
PoC changes
fix.diff documented (fix in verdict) in findings/poc/DF-0583/; batched into ../_batch_low/combined_all.patch
Verified recommended fix
Add a frm[1]>=sizeof(struct ieee80211_ath_ie) guard in the ath IE case.
Verdict
Source-confirmed: ieee80211_parse_ath derefs the IE as full struct ieee80211_ath_ie (needs 11B) without an IE-length guard. wlan (GENERIC).
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