[PATCH AUTOSEL 6.11 012/244] wifi: cfg80211: Set correct chandef when starting CAC

Sasha Levin
2024-09-25T11:37:12Z

From: Issam Hamdi <ih@simonwunderlich.de>

[ Upstream commit 20361712880396e44ce80aaeec2d93d182035651 ]

When starting CAC in a mode other than AP mode, it return a
"WARNING: CPU: 0 PID: 63 at cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211]"
caused by the chandef.chan being null at the end of CAC.

Solution: Ensure the channel definition is set for the different modes
when starting CAC to avoid getting a NULL 'chan' at the end of CAC.

Call Trace:
? show_regs.part.0+0x14/0x16
? __warn+0x67/0xc0
? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211]
? report_bug+0xa7/0x130
? exc_overflow+0x30/0x30
? handle_bug+0x27/0x50
? exc_invalid_op+0x18/0x60
? handle_exception+0xf6/0xf6
? exc_overflow+0x30/0x30
? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211]
? exc_overflow+0x30/0x30
? cfg80211_chandef_dfs_usable+0x20/0xaf [cfg80211]
? regulatory_propagate_dfs_state.cold+0x1b/0x4c [cfg80211]
? cfg80211_propagate_cac_done_wk+0x1a/0x30 [cfg80211]
? process_one_work+0x165/0x280
? worker_thread+0x120/0x3f0
? kthread+0xc2/0xf0
? process_one_work+0x280/0x280
? kthread_complete_and_exit+0x20/0x20
? ret_from_fork+0x19/0x24

Reported-by: Kretschmer Mathias <mathias.kretschmer@fit.fraunhofer.de>
Signed-off-by: Issam Hamdi <ih@simonwunderlich.de>
Link: https://patch.msgid.link/20240816142418.3381951-1-ih@simonwunderlich.de
[shorten subject, remove OCB, reorder cases to match previous list]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/wireless/nl80211.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 7397a372c78eb..b368e23847ddb 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -10143,7 +10143,20 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,

err = rdev_start_radar_detection(rdev, dev, &chandef, cac_time_ms);
if (!err) {
- wdev->links[0].ap.chandef = chandef;
+ switch (wdev->iftype) {
+ case NL80211_IFTYPE_AP:
+ case NL80211_IFTYPE_P2P_GO:
+ wdev->links[0].ap.chandef = chandef;
+ break;
+ case NL80211_IFTYPE_ADHOC:
+ wdev->u.ibss.chandef = chandef;
+ break;
+ case NL80211_IFTYPE_MESH_POINT:
+ wdev->u.mesh.chandef = chandef;
+ break;
+ default:
+ break;
+ }
wdev->cac_started = true;
wdev->cac_start_time = jiffies;
wdev->cac_time_ms = cac_time_ms;
--
2.43.0