From 1f9d7265b60bd0884247d1a3f23176ecd69b090f Mon Sep 17 00:00:00 2001 From: Rameshkumar Sundaram Date: Mon, 11 Apr 2022 14:37:51 +0530 Subject: [PATCH] UPSTREAM: cfg80211: hold bss_lock while updating nontrans_list Synchronize additions to nontrans_list of transmitting BSS with bss_lock to avoid races. Also when cfg80211_add_nontrans_list() fails __cfg80211_unlink_bss() needs bss_lock to be held (has lockdep assert on bss_lock). So protect the whole block with bss_lock to avoid races and warnings. Found during code review. Bug: 254441685 Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Signed-off-by: Rameshkumar Sundaram Link: https://lore.kernel.org/r/1649668071-9370-1-git-send-email-quic_ramess@quicinc.com Signed-off-by: Johannes Berg (cherry picked from commit a5199b5626cd6913cf8776a835bc63d40e0686ad) Signed-off-by: Lee Jones Change-Id: I06b4d5f79fa97b11b2aff61e4f060e8eaca719b2 --- net/wireless/scan.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 80221d7e345c..649afb08c0f1 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1388,11 +1388,13 @@ cfg80211_inform_single_bss_data(struct wiphy *wiphy, /* this is a nontransmitting bss, we need to add it to * transmitting bss' list if it is not there */ + spin_lock_bh(&rdev->bss_lock); if (cfg80211_add_nontrans_list(non_tx_data->tx_bss, &res->pub)) { if (__cfg80211_unlink_bss(rdev, res)) rdev->bss_generation++; } + spin_unlock_bh(&rdev->bss_lock); } trace_cfg80211_return_bss(&res->pub);