From: Tobias Herzog <t-herzog@gmx.de>
To: oneukum@suse.com
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH 2/4] cdc-acm: fix possible invalid access when processing notification
Date: Tue, 14 Mar 2017 21:14:47 +0100 [thread overview]
Message-ID: <1489522489-6233-2-git-send-email-t-herzog@gmx.de> (raw)
In-Reply-To: <1489522489-6233-1-git-send-email-t-herzog@gmx.de>
Notifications may only be 8 bytes so long. Accessing the 9th and
10th byte of unimplemented/unknown notifications may be insecure.
Also check the length of known notifications before accessing anything
behind the 8th byte.
Signed-off-by: Tobias Herzog <t-herzog@gmx.de>
---
drivers/usb/class/cdc-acm.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 40714fe..b99127e 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -296,6 +296,12 @@ static void acm_process_notification(struct acm *acm, unsigned char *buf)
break;
case USB_CDC_NOTIFY_SERIAL_STATE:
+ if (dr->wLength != 2) {
+ dev_dbg(&acm->control->dev,
+ "%s - malformed serial state\n", __func__);
+ break;
+ }
+
newctrl = get_unaligned_le16(data);
if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
@@ -332,11 +338,10 @@ static void acm_process_notification(struct acm *acm, unsigned char *buf)
default:
dev_dbg(&acm->control->dev,
- "%s - unknown notification %d received: index %d "
- "len %d data0 %d data1 %d\n",
+ "%s - unknown notification %d received: index %d len %d\n",
__func__,
dr->bNotificationType, dr->wIndex,
- dr->wLength, data[0], data[1]);
+ dr->wLength);
}
}
--
2.1.4
next prev parent reply other threads:[~2017-03-14 20:16 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1479118868.21146.4.camel@suse.com>
2017-03-14 20:14 ` [PATCH 1/4] cdc-acm: reassemble fragmented notifications Tobias Herzog
2017-03-14 20:14 ` Tobias Herzog [this message]
2017-03-15 9:26 ` [PATCH 2/4] cdc-acm: fix possible invalid access when processing notification Oliver Neukum
2017-03-14 20:14 ` [PATCH 3/4] cdc-acm: log message for serial state notification Tobias Herzog
2017-03-14 20:14 ` [PATCH 4/4] cdc-acm: remove unused element of struct acm Tobias Herzog
2017-03-15 9:26 ` [PATCH 1/4] cdc-acm: reassemble fragmented notifications Oliver Neukum
2017-03-18 18:52 ` Tobias Herzog
2017-03-18 18:52 ` [PATCH v2 0/4] " Tobias Herzog
2017-03-18 18:52 ` [PATCH v2 1/4] " Tobias Herzog
2017-03-20 15:02 ` Oliver Neukum
2017-03-24 21:50 ` Tobias Herzog
2017-03-28 8:04 ` Oliver Neukum
2017-03-18 18:52 ` [PATCH v2 2/4] cdc-acm: fix possible invalid access when processing notification Tobias Herzog
2017-03-19 9:50 ` Sergei Shtylyov
2017-03-20 15:04 ` Oliver Neukum
2017-03-18 18:52 ` [PATCH v2 3/4] cdc-acm: log message for serial state notification Tobias Herzog
2017-03-18 18:52 ` [PATCH v2 4/4] cdc-acm: remove unused element of struct acm Tobias Herzog
2017-03-30 20:15 ` [PATCH v3 0/4] cdc-acm: reassemble fragmented notifications Tobias Herzog
2017-03-30 20:15 ` [PATCH v3 1/4] cdc-acm: fix possible invalid access when processing notification Tobias Herzog
2017-03-31 9:31 ` Oliver Neukum
2017-03-30 20:15 ` [PATCH v3 2/4] cdc-acm: reassemble fragmented notifications Tobias Herzog
2017-03-31 9:33 ` Oliver Neukum
2017-03-30 20:15 ` [PATCH v3 3/4] cdc-acm: log message for serial state notification Tobias Herzog
2017-03-31 9:34 ` Oliver Neukum
2017-03-30 20:15 ` [PATCH v3 4/4] cdc-acm: remove unused element of struct acm Tobias Herzog
2017-03-31 9:35 ` Oliver Neukum
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