diff mbox series

[v2,wireless,1/5] wifi: mac80211: flush the station before moving it to UN-AUTHORIZED state

Message ID 20250306123626.450bc40e8b04.I636ba96843c77f13309c15c9fd6eb0c5a52a7976@changeid (mailing list archive)
State Accepted
Delegated to: Johannes Berg
Headers show
Series wifi: mac0211/cfg80211: bugfixes - 2025-03-06 | expand

Checks

Context Check Description
wifibot/tree_selection success Clearly marked for wireless
wifibot/ynl success Generated files up to date; no warnings/errors; no diff in generated;
wifibot/fixes_present success Fixes tag present in non-next series
wifibot/series_format success Posting correctly formatted
wifibot/build_32bit success Errors and warnings before: 0 this patch: 0
wifibot/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
wifibot/build_clang success Errors and warnings before: 0 this patch: 0
wifibot/build_clang_rust success No Rust files in patch. Skipping build
wifibot/build_tools success No tools touched, skip
wifibot/check_selftest success No net selftest shell script
wifibot/checkpatch success total: 0 errors, 0 warnings, 0 checks, 39 lines checked
wifibot/deprecated_api success None detected
wifibot/header_inline success No static functions without inline keyword in header files
wifibot/kdoc success Errors and warnings before: 0 this patch: 0
wifibot/source_inline success Was 0 now: 0
wifibot/verify_fixes success No Fixes tag
wifibot/verify_signedoff success Signed-off-by tag matches author and committer

Commit Message

Miri Korenblit March 6, 2025, 10:37 a.m. UTC 
From: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

We first want to flush the station to make sure we no longer have any
frames being Tx by the station before the station is moved to
un-authorized state. Failing to do that will lead to races: a frame may
be sent after the station's state has been changed.

Since the API clearly states that the driver can't fail the sta_state()
transition down the list of state, we can easily flush the station
first, and only then call the driver's sta_state().

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
---
 net/mac80211/sta_info.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index f83268fa9f92..caa3d0236b5e 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -4,7 +4,7 @@ 
  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
  * Copyright (C) 2015 - 2017 Intel Deutschland GmbH
- * Copyright (C) 2018-2023 Intel Corporation
+ * Copyright (C) 2018-2024 Intel Corporation
  */
 
 #include <linux/module.h>
@@ -1335,9 +1335,13 @@  static int _sta_info_move_state(struct sta_info *sta,
 		sta->sta.addr, new_state);
 
 	/* notify the driver before the actual changes so it can
-	 * fail the transition
+	 * fail the transition if the state is increasing.
+	 * The driver is required not to fail when the transition
+	 * is decreasing the state, so first, do all the preparation
+	 * work and only then, notify the driver.
 	 */
-	if (test_sta_flag(sta, WLAN_STA_INSERTED)) {
+	if (new_state > sta->sta_state &&
+	    test_sta_flag(sta, WLAN_STA_INSERTED)) {
 		int err = drv_sta_state(sta->local, sta->sdata, sta,
 					sta->sta_state, new_state);
 		if (err)
@@ -1413,6 +1417,16 @@  static int _sta_info_move_state(struct sta_info *sta,
 		break;
 	}
 
+	if (new_state < sta->sta_state &&
+	    test_sta_flag(sta, WLAN_STA_INSERTED)) {
+		int err = drv_sta_state(sta->local, sta->sdata, sta,
+					sta->sta_state, new_state);
+
+		WARN_ONCE(err,
+			  "Driver is not allowed to fail if the sta_state is transitioning down the list: %d\n",
+			  err);
+	}
+
 	sta->sta_state = new_state;
 
 	return 0;