diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-09-21 16:58:48 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-12 11:27:33 +0200 |
| commit | feab51a916ed07219dee38b898fe22bd2a98193a (patch) | |
| tree | e89433e978e81e8ee0d893f940c7934712c95743 /drivers/net/usb/usbnet.c | |
| parent | 5d9a9c3dcc1f63215b5a5b877be589974ec4f31d (diff) | |
USB: core: harden cdc_parse_cdc_header
commit 2e1c42391ff2556387b3cb6308b24f6f65619feb upstream.
Andrey Konovalov reported a possible out-of-bounds problem for the
cdc_parse_cdc_header function. He writes:
It looks like cdc_parse_cdc_header() doesn't validate buflen
before accessing buffer[1], buffer[2] and so on. The only check
present is while (buflen > 0).
So fix this issue up by properly validating the buffer length matches
what the descriptor says it is.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/usb/usbnet.c')
| -rw-r--r-- | drivers/net/usb/usbnet.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index c2ea4e5666fb..9710cf71054a 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1990,6 +1990,10 @@ int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, elength = 1; goto next_desc; } + if ((buflen < elength) || (elength < 3)) { + dev_err(&intf->dev, "invalid descriptor buffer length\n"); + break; + } if (buffer[1] != USB_DT_CS_INTERFACE) { dev_err(&intf->dev, "skipping garbage\n"); goto next_desc; |