diff options
| author | Siddh Raman Pant <code@siddh.me> | 2022-08-14 18:15:12 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-15 13:04:53 +0300 |
| commit | 66689c5c02acd4d76c28498fe220998610aec61e (patch) | |
| tree | 675157830fc2a2866965e260573ab8333196b815 /net/mac80211 | |
| parent | 1142f04f920c174d1cf79e54f07abf581dcbe1dd (diff) | |
| download | linux-66689c5c02acd4d76c28498fe220998610aec61e.tar.xz | |
wifi: mac80211: Don't finalize CSA in IBSS mode if state is disconnected
commit 15bc8966b6d3a5b9bfe4c9facfa02f2b69b1e5f0 upstream.
When we are not connected to a channel, sending channel "switch"
announcement doesn't make any sense.
The BSS list is empty in that case. This causes the for loop in
cfg80211_get_bss() to be bypassed, so the function returns NULL
(check line 1424 of net/wireless/scan.c), causing the WARN_ON()
in ieee80211_ibss_csa_beacon() to get triggered (check line 500
of net/mac80211/ibss.c), which was consequently reported on the
syzkaller dashboard.
Thus, check if we have an existing connection before generating
the CSA beacon in ieee80211_ibss_finish_csa().
Cc: stable@vger.kernel.org
Fixes: cd7760e62c2a ("mac80211: add support for CSA in IBSS mode")
Link: https://syzkaller.appspot.com/bug?id=05603ef4ae8926761b678d2939a3b2ad28ab9ca6
Reported-by: syzbot+b6c9fe29aefe68e4ad34@syzkaller.appspotmail.com
Signed-off-by: Siddh Raman Pant <code@siddh.me>
Tested-by: syzbot+b6c9fe29aefe68e4ad34@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20220814151512.9985-1-code@siddh.me
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/mac80211')
| -rw-r--r-- | net/mac80211/ibss.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c index 0e26c83b6b41..d5b8568591d4 100644 --- a/net/mac80211/ibss.c +++ b/net/mac80211/ibss.c @@ -542,6 +542,10 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) sdata_assert_lock(sdata); + /* When not connected/joined, sending CSA doesn't make sense. */ + if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) + return -ENOLINK; + /* update cfg80211 bss information with the new channel */ if (!is_zero_ether_addr(ifibss->bssid)) { cbss = cfg80211_get_bss(sdata->local->hw.wiphy, |