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 06F4F423782; Thu, 30 Jul 2026 15:01:53 +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=1785423714; cv=none; b=TMXQErqV74IYeFzWOxZyWW+VY2gAiG7+7lMZnFkJJMZ3gyNoc7KuEfwcDipta4dxRSRNIQ7Fwn4aCUUMRpN4i8L1QaZUAhh/9T6P5GQMsmqOzt+dIYwHEaAe7Mxp6idlN2kkvXguYKwrq/AIcLJT2NdhXHwRORwXuKzCXTP2UNU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423714; c=relaxed/simple; bh=YulG9bRmGL2z12hp6ZVhu/ldYc4AHhIovku9r9G6D6g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bwBuZCGLbjVyGtcuJYZqpaWLGvRQg5iSxR+wWd2WTcvUKln5kem6jbFzQtT8C1FSNix6w4d5vGrRDcsQvbUZzsQb15YhJJWzw5fIpMhVMlt/IX4WKAaLXk45fEQsIIiuGkYFv4R495ry1+FjyJ69B8xGm7w8Qke6Q/5yLVbomw8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jcgXtW0d; 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="jcgXtW0d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 538D91F000E9; Thu, 30 Jul 2026 15:01:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785423712; bh=QMfxXi4ELoiy1KD7LB8iMMSCn8V+3JtTsw4pWhsJxPo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jcgXtW0dyIvJI1NanCeRpLBXdfH2KcXLtAx4iusr/o3z/9cOI9HfJFO+FBh2E8atO DcMrEihH6R3eQ5n9guWnWHZD28OFMOZVRENF0hmaMEP6qWJuyoLqYODdvKPGGrZ9eD CYtd67lkib8dYb/dLOy00X3htSN55Vgcq3rX9F5A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , "Chia-Lin Kao (AceLan)" , Heikki Krogerus Subject: [PATCH 6.18 141/675] usb: core: port: Deattach Type-C connector on component unbind Date: Thu, 30 Jul 2026 16:07:51 +0200 Message-ID: <20260730141448.133786340@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: patches@lists.linux.dev 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: Chia-Lin Kao (AceLan) commit e0b291fe117964037e0ba382eff4bb365d531c3a upstream. connector_unbind() is the mirror of connector_bind(), but it is missing the symmetric call to typec_deattach() that connector_bind() makes via: if (port_dev->child) typec_attach(port_dev->connector, &port_dev->child->dev); When a Thunderbolt dock is unplugged, two teardown paths race: 1. The component framework calls connector_unbind() first, which sets port_dev->connector = NULL without calling typec_deattach(). This leaves port->usb2_dev/port->usb3_dev in struct typec_port pointing at the USB device that is about to be freed. 2. usb_disconnect() then calls typec_deattach(port_dev->connector, ...), but port_dev->connector is already NULL, so the call is a no-op and port->usb2_dev is never cleared. 3. Concurrently, UCSI detects a PD partner-disconnect event and calls typec_unregister_partner(), which reads port->usb2_dev (now a dangling pointer to freed memory) and passes it to typec_partner_unlink_device() -> sysfs_remove_link() -> dev_name() on the freed device, corrupting the typec/UCSI partner state. This corruption leaves the Thunderbolt tunnel in an inconsistent state on the next dock hot-plug. On affected hardware the dock's I225/igc NIC fails to enumerate: AER fires a slot reset while the igc driver is still initialising ("PCIe link lost"), and the subsequent igc_reset attempt hits igc_rd32 on an already-detached device: igc 0000:2e:00.0 eth0: PCIe link lost, device now detached igc: Failed to read reg 0x0! WARNING: CPU: 9 PID: 129 at drivers/net/ethernet/intel/igc/igc_main.c:7005 igc_rd32+0xa4/0xc0 [igc] Call Trace: igc_disable_pcie_master+0x16/0xa0 [igc] igc_reset_hw_base+0x14/0x170 [igc] igc_reset+0x63/0x110 [igc] igc_io_slot_reset+0x9e/0xd0 [igc] report_slot_reset+0x5d/0xc0 pcie_do_recovery+0x209/0x400 aer_isr_one_error_type+0x235/0x430 aer_isr+0x4e/0x80 irq_thread+0xf4/0x1f0 4. UCSI later handles the PD partner-disconnect and calls typec_unregister_partner(), which still sees the stale port->usb2_dev and tries to remove its sysfs link a second time: kernfs: can not remove 'typec', no directory WARNING: CPU: 6 PID: 55 at fs/kernfs/dir.c:1706 kernfs_remove_by_name_ns+0xe9/0xf0 Workqueue: events ucsi_handle_connector_change [typec_ucsi] Call Trace: sysfs_remove_link+0x19/0x50 typec_unregister_partner+0x6e/0x120 [typec] ucsi_unregister_partner+0x107/0x150 [typec_ucsi] ucsi_handle_connector_change+0x3ec/0x490 [typec_ucsi] process_one_work+0x18e/0x3e0 worker_thread+0x2e3/0x420 kthread+0x10a/0x230 ret_from_fork+0x121/0x140 ret_from_fork_asm+0x1a/0x30 With worse timing the same stale pointer is dereferenced after the backing memory is freed, turning the warning into a use-after-free. Fix the asymmetry: call typec_deattach() before clearing port_dev->connector, matching what connector_bind() does on the bind side. typec_partner_deattach() is already protected by port->partner_link_lock, so it serialises safely with the concurrent typec_unregister_partner() path. Fixes: 11110783f5ea ("usb: Inform the USB Type-C class about enumerated devices") Cc: stable Signed-off-by: Chia-Lin Kao (AceLan) Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20260611071201.1235545-1-acelan.kao@canonical.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/port.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/usb/core/port.c +++ b/drivers/usb/core/port.c @@ -726,6 +726,8 @@ static void connector_unbind(struct devi sysfs_remove_link(&connector->kobj, dev_name(dev)); sysfs_remove_link(&dev->kobj, "connector"); + if (port_dev->child) + typec_deattach(port_dev->connector, &port_dev->child->dev); port_dev->connector = NULL; }