diff options
author | Tobias Herzog <t-herzog@gmx.de> | 2017-03-30 22:15:10 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-05-25 15:44:36 +0200 |
commit | 809ae061d998359783c1bb0c52bba14f4a6397c4 (patch) | |
tree | 96f2da7d48e5e0954989c66b3595e63af8e49141 /drivers/usb/class | |
parent | 198ab4031873b5511d6ef9b4777cabc4eebcaf18 (diff) |
cdc-acm: fix possible invalid access when processing notification
commit 1bb9914e1730417d530de9ed37e59efdc647146b upstream.
Notifications may only be 8 bytes 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>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/class')
-rw-r--r-- | drivers/usb/class/cdc-acm.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index c5ff13f22b24..a876d47246dc 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -311,6 +311,12 @@ static void acm_ctrl_irq(struct urb *urb) break; case USB_CDC_NOTIFY_SERIAL_STATE: + if (le16_to_cpu(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)) { @@ -347,11 +353,10 @@ static void acm_ctrl_irq(struct urb *urb) 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->bNotificationType, dr->wIndex, dr->wLength); + break; } exit: |