Add KUnit coverage for ieee80211_parse_neg_ttlm() to lock the sparse
link_map_presence layout against future regressions.
The sparse_presence_no_oob_read case crafts a negotiated TTLM element
with link_map_presence = BIT(0) | BIT(7) and bm_size = 2 in a buffer
sized exactly to the validated element length. Without the parser
fix this would read 14 bytes past the buffer when processing TID 7;
under KASAN that is a slab-out-of-bounds report.
The dense_presence_baseline case crafts a fully populated
link_map_presence = 0xff element to confirm that the cursor-advance
fix does not regress the path that was already correct.
Export ieee80211_parse_neg_ttlm via VISIBLE_IF_MAC80211_KUNIT so the
test can call it directly.
Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260515151719.1317659-3-michael.bommarito@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>