linux-kernel - [PATCH 3.4 096/134] usb: hub: Clear Port Reset Change during init/resume

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20140410032312.031855798@linuxfoundation.org>
Date:	Wed,  9 Apr 2014 20:23:32 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Julius Werner <jwerner@...omium.org>,
	Alan Stern <stern@...land.harvard.edu>,
	Ben Hutchings <ben@...adent.org.uk>,
	Yang Yingliang <yangyingliang@...wei.com>
Subject: [PATCH 3.4 096/134] usb: hub: Clear Port Reset Change during init/resume

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Julius Werner <jwerner@...omium.org>

commit e92aee330837e4911553761490a8fb843f2053a6 upstream.

This patch adds the Port Reset Change flag to the set of bits that are
preemptively cleared on init/resume of a hub. In theory this bit should
never be set unexpectedly... in practice it can still happen if BIOS,
SMM or ACPI code plays around with USB devices without cleaning up
correctly. This is especially dangerous for XHCI root hubs, which don't
generate any more Port Status Change Events until all change bits are
cleared, so this is a good precaution to have (similar to how it's
already done for the Warm Port Reset Change flag).

Signed-off-by: Julius Werner <jwerner@...omium.org>
Acked-by: Alan Stern <stern@...land.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
[bwh: Backported to 3.2:
 - Adjust context
 - s/usb_clear_port_feature/clear_port_feature/]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
[yangyl: Backported to 3.4: Adjust context]
Signed-off-by: Yang Yingliang <yangyingliang@...wei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/usb/core/hub.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -920,6 +920,11 @@ static void hub_activate(struct usb_hub
 			clear_port_feature(hub->hdev, port1,
 					USB_PORT_FEAT_C_ENABLE);
 		}
+		if (portchange & USB_PORT_STAT_C_RESET) {
+			need_debounce_delay = true;
+			clear_port_feature(hub->hdev, port1,
+					USB_PORT_FEAT_C_RESET);
+		}
 		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
 				hub_is_superspeed(hub->hdev)) {
 			need_debounce_delay = true;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/