From: Johannes Berg <johannes.berg@xxxxxxxxx> If the FTM responder settings are changed simultaneously with the CSA beacon, the buffer size allocated isn't sufficient and we'll have a heap overrun. Fix this. While at it, also clean up the ftm_responder assignment, doing it only if ftm_responder is non-zero is valid as it's 0 to start with, but not really useful to understand the code. Fixes: bc847970f432 ("mac80211: support FTM responder configuration/statistics") Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> --- net/mac80211/cfg.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 51622333d460..818aa0060349 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -2891,7 +2891,7 @@ cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon) len = beacon->head_len + beacon->tail_len + beacon->beacon_ies_len + beacon->proberesp_ies_len + beacon->assocresp_ies_len + - beacon->probe_resp_len; + beacon->probe_resp_len + beacon->lci_len + beacon->civicloc_len; new_beacon = kzalloc(sizeof(*new_beacon) + len, GFP_KERNEL); if (!new_beacon) @@ -2934,8 +2934,9 @@ cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon) memcpy(pos, beacon->probe_resp, beacon->probe_resp_len); pos += beacon->probe_resp_len; } - if (beacon->ftm_responder) - new_beacon->ftm_responder = beacon->ftm_responder; + + /* might copy -1, meaning no changes requested */ + new_beacon->ftm_responder = beacon->ftm_responder; if (beacon->lci) { new_beacon->lci_len = beacon->lci_len; new_beacon->lci = pos; -- 2.17.2