From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1929F52940E; Wed, 23 Sep 2026 14:14:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790172879; cv=none; b=YXnKWINFa92FdtVli1kGWNERm+bWwMwXJGDNvT9UwoXZJhhZtSrS9z2lzMgXHoJq4o+LKYpuuOQRfrBFcBoBoEkz1POK7raV52ArqnxdGm0r1SE4gOIeU7IqgWJTWh4FJ+9XPE46yu2+T8HSVASuMGTix9r4PorxSpdqpwz7f9c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790172879; c=relaxed/simple; bh=uCEKuTxej8dctPxgRl0fx3bKYqxsp/wtMjy+UtA9fuU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LRx7RSEGIvPXUCzd8P4fZkQMp4MuuDqeioaESeXr7HFWrLgcwoRcJ/nHpz1SQKWHLiJ1WVESLCbStjWTWVdHBwPZ4BkNC5b/wo5a0I3AcLZgnRYDxKTtwrpWg2B+GpJqnBrsqpzsgc6dsVDd6NqYG6fdwsjLZOb65rWEz7i75BY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ESJSF02O; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ESJSF02O" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 655A41F000FF; Wed, 23 Sep 2026 14:14:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790172878; bh=RmMtLV+orf9DsoYvDbAxm8Q01Ro6xH+9XrvbzJiHdzw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ESJSF02OmHBkipR1PFM6muVaQFmh5cZdMDCeDB6DQ/kVBmU+bbaYwClbC7XnKQi5b wKy+v6sPK1zEsKQRP4Tzy2W74cRP95VvintLWdSrDEOdDrKP/Ravdj00EeaQMmGa4p eae17ja2oJDsZThyUQLqRMhUkFRqO+A6HpFXVncg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Johannes Berg , Sasha Levin Subject: [PATCH 7.2 079/438] wifi: mac80211: unlist vifs when their netdev is unregistered Date: Wed, 23 Sep 2026 16:01:40 +0200 Message-ID: <20260923140646.832581980@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140644.756254324@linuxfoundation.org> References: <20260923140644.756254324@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg [ Upstream commit eee2efd82867b623982ac51925b5a1812a74c50d ] mac80211 only removes vifs from the local->interfaces list when an interface is removed via ieee80211_if_remove(), before it unregisters the netdev. However, it's possible for a netdev to be unregistered without going through that: When the netns that holds the wiphy is destroyed, the wiphy is supposed to move to the init_ns, but that can run into allocation failures. Then, mac80211 has an interface listed that doesn't exist, and will eventually hit BUG: failure at net/wireless/core.h:141/wiphy_to_rdev()! ... _cfg80211_unregister_wdev+0x24/0x36a [cfg80211] cfg80211_unregister_wdev+0x15/0x1d [cfg80211] ieee80211_remove_interfaces+0x1ff/0x257 [mac80211] ieee80211_unregister_hw+0x73/0x1d1 [mac80211] mac80211_hwsim_del_radio+0x114/0x166 [mac80211_hwsim] Remove the interface from the list in ->ndo_uninit if it's still around to avoid this. Assisted-by: LLM Fixes: 463d018323851 ("cfg80211: make aware of net namespaces") Link: https://patch.msgid.link/20260904170220.038ad73e6c04.I990abca78483e058746b6f42b4796717c3028164@changeid Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/iface.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 4c34c3287eb4a..842bfb4a7cb68 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -924,9 +924,33 @@ static void ieee80211_teardown_sdata(struct ieee80211_sub_if_data *sdata) } } +/* + * The netdev can be unregistered without mac80211 doing it, e.g. by the netdev + * core when cfg80211 couldn't move it out of a network namespace that's being + * destroyed. Drop it from the interface list either way. + */ +static void ieee80211_unlist_sdata(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_sub_if_data *iter; + + ASSERT_RTNL(); + + list_for_each_entry(iter, &local->interfaces, list) { + if (iter != sdata) + continue; + guard(mutex)(&local->iflist_mtx); + list_del_rcu(&sdata->list); + return; + } +} + static void ieee80211_uninit(struct net_device *dev) { - ieee80211_teardown_sdata(IEEE80211_DEV_TO_SUB_IF(dev)); + struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); + + ieee80211_unlist_sdata(sdata); + ieee80211_teardown_sdata(sdata); } static int ieee80211_netdev_setup_tc(struct net_device *dev, -- 2.53.0