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 11:51:17 +0200 |
| commit | 767f7a2cf33a135fe3f57010b51c3f6e92d7677d (patch) | |
| tree | 98a847a5c5fb9f8eb41923b8caf6fd27c9a5284f /drivers/usb/core/message.c | |
| parent | d77606e93d819ad4b8f57511ff61a629ced49750 (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/usb/core/message.c')
| -rw-r--r-- | drivers/usb/core/message.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 3a4707746157..4c388451f31f 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -2068,6 +2068,10 @@ 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; |