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 249F643F4CD; Thu, 30 Jul 2026 15:23:45 +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=1785425026; cv=none; b=bUBOyXPggkwJuQOmp9jGHLkfN97JfAihDqMGimHrQVA7fmCBLQuwIHTE3Ths2yskIF0uDRpMWpIVVGOGb6VVyxmprVcEGznphxZn+eNRoWBMaqczuFoXDIqo+cpckwCyNgTVBkgm2QSXs4Fa7SJGhVUixgChVZb+h5G1CWXF2eI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785425026; c=relaxed/simple; bh=7z6qG27a9NjpFMxLaxBzrmMt02/X3hh0Dmyqh0simR8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S8KDyLD5Adw65grk6qLZLrCinitoEjvkcpW0l8hxiVRJsy6U4Ksmp8+3eiEKNzBpWzXcLEljSxS71yH/40PNOL707/kbkvXEp7ZAOg+aKsMGi+Fuc0uO5IqlagNO+z+wOOqyREx2yAWI4u2gJUnZYCg6sJYopaWsFkDPOmVUtL0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=y9+Egv19; 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="y9+Egv19" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 800181F000E9; Thu, 30 Jul 2026 15:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785425025; bh=Jk9IJxht+qaGqJCTfOn6WgwM7QnPdNrF0Qo1wmS/rtE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=y9+Egv19TJ2fa5Ah8JGKoOBIp5Prgb92b/ohqJMzPb7IIpWAozBhjCh4WB2n0rgjw lAGTQC6QEPH417GZWXj3JxW6QvQBsy7X7UXqYQ4ccnq1k+mrMh++oQmbpKGQLYvoUq rKRk9YQYN+f5IBYPQTtQYDOpp2n65Eo9LpzAWIMk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ibrahim Hashimov , Jakub Kicinski Subject: [PATCH 6.18 556/675] mac802154: hold an interface reference across the scan worker Date: Thu, 30 Jul 2026 16:14:46 +0200 Message-ID: <20260730141456.954174307@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ibrahim Hashimov commit 234e5e898b713bc0b3a631b6f002897f43d046c8 upstream. mac802154_scan_worker() captures the scanning sub-interface under RCU and then keeps dereferencing sdata->dev after rcu_read_unlock() and outside the rtnl -- in the failure traces, in mac802154_transmit_beacon_req() (skb->dev = sdata->dev), and in the end_scan cleanup. Nothing keeps that netdev alive across the worker iteration. A concurrent DEL_INTERFACE or PHY removal can unregister the interface once the worker drops the rtnl between its two drv_set_channel() sections. unregister_netdevice() frees the netdev asynchronously from netdev_run_todo() with the rtnl already dropped, so neither holding the rtnl nor the per-PHY IEEE802154_IS_SCANNING flag prevents a stale worker iteration from dereferencing the freed netdev -- a KASAN slab-use-after-free, reachable by racing TRIGGER_SCAN against DEL_INTERFACE (both CAP_NET_ADMIN). Pin the netdev with netdev_hold() while the RCU read lock is still held, and release it at every worker exit. Fixes: 57588c71177f ("mac802154: Handle passive scanning") Cc: stable@vger.kernel.org Signed-off-by: Ibrahim Hashimov Link: https://patch.msgid.link/20260721211228.34578-1-security@auditcode.ai Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/mac802154/scan.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/net/mac802154/scan.c +++ b/net/mac802154/scan.c @@ -179,6 +179,7 @@ void mac802154_scan_worker(struct work_s enum nl802154_scan_types scan_req_type; struct ieee802154_sub_if_data *sdata; unsigned int scan_duration = 0; + netdevice_tracker dev_tracker; struct wpan_phy *wpan_phy; u8 scan_req_duration; u8 page, channel; @@ -209,6 +210,14 @@ void mac802154_scan_worker(struct work_s return; } + /* + * sdata->dev is dereferenced below after rcu_read_unlock() and outside + * the rtnl, and a concurrent DEL_INTERFACE / PHY teardown can free it + * asynchronously from netdev_run_todo(). Pin it with a reference taken + * while the RCU read lock is still held, and drop it at every exit. + */ + netdev_hold(sdata->dev, &dev_tracker, GFP_ATOMIC); + wpan_phy = scan_req->wpan_phy; scan_req_type = scan_req->type; scan_req_duration = scan_req->duration; @@ -262,12 +271,14 @@ void mac802154_scan_worker(struct work_s "Scan page %u channel %u for %ums\n", page, channel, jiffies_to_msecs(scan_duration)); queue_delayed_work(local->mac_wq, &local->scan_work, scan_duration); + netdev_put(sdata->dev, &dev_tracker); return; end_scan: rtnl_lock(); mac802154_scan_cleanup_locked(local, sdata, false); rtnl_unlock(); + netdev_put(sdata->dev, &dev_tracker); } int mac802154_trigger_scan_locked(struct ieee802154_sub_if_data *sdata,