diff options
author | Tobias Herzog <t-herzog@gmx.de> | 2017-03-30 22:15:10 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-01 11:05:03 +0200 |
commit | 1bb9914e1730417d530de9ed37e59efdc647146b (patch) | |
tree | 86657e8ac8ebd75547ee47dd558b6ff360228857 /drivers/usb/class | |
parent | 2f86a96be0ccb1302b7eee7855dbee5ce4dc5dfb (diff) |
cdc-acm: fix possible invalid access when processing notification
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>
Cc: stable <stable@vger.kernel.org>
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 00d55ba8983f..cdabe76960bc 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -323,6 +323,12 @@ 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)) { @@ -359,11 +365,10 @@ 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: |