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 916EF3806BD; Thu, 30 Jul 2026 15:49:41 +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=1785426582; cv=none; b=BtTUDhavFtUKW306aZ/S+8ykblRWeTV1aKr9n4D2LcXTuryHXuxAvnibSbwD71TrlAyiwu9xE5n/TnX/rKc2GbL93j70wMPUxlbb17U+cZxRp0Ba9O02zF1HYJ9q7o2MuTRdKbMGey6eQGXCdqWzenw7jqzf+mj/qtvtzg1nlMY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785426582; c=relaxed/simple; bh=9ZOp4aC0PswJ0DbbHOdSeaAg53m4Upcn2LsO8coaDsA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NjhK2KcmlFXsqg2LIvbhALTi2WJ1CNt2rwZF0CIt6Jm10o3Vl1tgp5h/dtaUpS9nND0nZnQEkaWcLngufdU1DX460PcWz+LILL83uDe8dAPIwK+wSqgHz6eGkIA46seAMvNV0dWoZJ/DXhBM8/l+V6wIMN0kwKVxa072wG/TYu8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IdqKW6EE; 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="IdqKW6EE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC7B61F000E9; Thu, 30 Jul 2026 15:49:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785426581; bh=OhV+UOZ6n1BynsGIy7mECTfNwYCLjA8hwgSJyUo6bMU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=IdqKW6EEPg8J5OxrRgWqgDUFtC6PcofQeF6m5wR9k0MquAeFQ5GoglS9CrvjqzbOn pja7KAdZE0vb/o1pIjkeJt/AlrgUHzWM0aCzeLeRCU8i/v0EJ3xK53mjEy6v6TkJ36 GIXMCLlQU1NFa2X+VbpNuJ3VVeNNBlQ7MgPO4eFE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ibrahim Hashimov , Jakub Kicinski Subject: [PATCH 6.12 425/602] mac802154: hold an interface reference across the scan worker Date: Thu, 30 Jul 2026 16:13:37 +0200 Message-ID: <20260730141444.895767654@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141435.976815864@linuxfoundation.org> References: <20260730141435.976815864@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 6.12-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,