diff options
| author | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2013-09-11 21:56:58 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-01-03 04:33:34 +0000 |
| commit | 0b568069764b25b7114b241c361a904838280639 (patch) | |
| tree | f148a12dc7ec051d3a7898c9d9d6e09f721e61bc | |
| parent | ebca8c26fb22fca588fdcf5e5baa409da399247f (diff) | |
HID: multitouch: validate indexes details
commit 8821f5dc187bdf16cfb32ef5aa8c3035273fa79a upstream.
When working on report indexes, always validate that they are in bounds.
Without this, a HID device could report a malicious feature report that
could trick the driver into a heap overflow:
[ 634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500
...
[ 676.469629] BUG kmalloc-192 (Tainted: G W ): Redzone overwritten
Note that we need to change the indexes from s8 to s16 as they can
be between -1 and 255.
CVE-2013-2897
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.2: mt_device::{cc,cc_value,inputmode}_index do not
exist and the corresponding indices do not need to be validated.
mt_device::maxcontact_report_id does not exist either. So all we need
to do is to widen mt_device::inputmode.]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | drivers/hid/hid-multitouch.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 13af0f1f08d..a605ba1e844 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -66,7 +66,7 @@ struct mt_device { unsigned last_field_index; /* last field index of the report */ unsigned last_slot_field; /* the last field of a slot */ int last_mt_collection; /* last known mt-related collection */ - __s8 inputmode; /* InputMode HID feature, -1 if non-existent */ + __s16 inputmode; /* InputMode HID feature, -1 if non-existent */ __u8 num_received; /* how many contacts we received */ __u8 num_expected; /* expected last contact index */ __u8 maxcontacts; |