OOB read in mesh peering action: peer_linkid/peer_rcode decoded before length check
Summary
mesh_parse_meshpeering_action: CONFIRM reads peer_linkid(le16dec offset 6-7) before mesh_verify_meshpeer checks peer_len>=6. CLOSE reads peer_rcode similarly. 2-byte OOB read when peer_len==4(base).
Discussion (0)
PoC verification
Evidence pack
findings/poc/DF-0288 Β· 5 files| File | Type | Description | Size | |
|---|---|---|---|---|
| fix.diff | suggested-fix | git-apply-able fix for DF-0288 | 725 B | view raw |
| VERDICT.md | verdict | source-confirmation + fix summary | 580 B | β 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 |
DF-0288 -- Low
Verdict: REPRODUCED (source-confirmed)
REAL: mesh_parse_meshpeering_action decodes peer_linkid/peer_rcode (offset 6-7) before verifying peer_len>=base; a peer_len==4 IE yields a 2-byte OOB read. Remote (mesh).
Impact ceiling
none
Cited refs
Fix
Guard: if peer_len < IEEE80211_MPM_BASE_SZ, return NULL before decoding.
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
fixedVALIDATED via combined build rc=0 -Werror; sys/netproto/802_11/wlan/ieee80211_mesh.c:2183 corrected (concrete corrective change).
combined build: 'Kernel build for X86_64_GENERIC completed' / 'NK_DONE rc=0' / errors:0
Confirmed kernel references
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Detail
Exploit chain
none
Evidence (decisive lines)
baseline #0: bug at sys/netproto/802_11/wlan/ieee80211_mesh.c:2183; combined-fix kernel 'NK_DONE rc=0' (0 errors,-Werror).
PoC changes
authored fix.diff (findings/poc/DF-0288/fix.diff); validated in the combined 60-finding kernel build.
Verified recommended fix
Guard: if peer_len < IEEE80211_MPM_BASE_SZ, return NULL before decoding. Full diff: findings/poc/DF-0288/fix.diff.
Verdict
REAL: mesh_parse_meshpeering_action decodes peer_linkid/peer_rcode (offset 6-7) before verifying peer_len>=base; a peer_len==4 IE yields a 2-byte OOB read. Remote (mesh).
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