Messages in this thread | | | Date | Wed, 5 Dec 2012 11:10:54 +0100 | Subject | Re: [PATCH 02/14] HID: i2c-hid: fix memory corruption due to missing hid declaration | From | Benjamin Tissoires <> |
| |
On Tue, Dec 4, 2012 at 10:42 PM, Jean Delvare <khali@linux-fr.org> wrote: > On Tue, 4 Dec 2012 16:27:43 +0100, Benjamin Tissoires wrote: >> HID descriptors contains 4 bytes of reserved field. >> The previous implementation was overriding the next fields in struct i2c_hid. >> >> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> >> --- >> drivers/hid/i2c-hid/i2c-hid.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c >> index 0fbb229..ad771a7 100644 >> --- a/drivers/hid/i2c-hid/i2c-hid.c >> +++ b/drivers/hid/i2c-hid/i2c-hid.c >> @@ -68,6 +68,7 @@ struct i2c_hid_desc { >> __le16 wVendorID; >> __le16 wProductID; >> __le16 wVersionID; >> + __le32 reserved; >> } __packed; >> >> struct i2c_hid_cmd { >> @@ -778,7 +779,7 @@ static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid) >> } >> >> dsize = le16_to_cpu(hdesc->wHIDDescLength); >> - if (!dsize || dsize > HID_MAX_DESCRIPTOR_SIZE) { >> + if (!dsize || dsize > sizeof(struct i2c_hid_desc)) { > > Shouldn't !dsize rather be dsize < 4? You're reading hdesc->bcdVersion, > which is only defined if dsize >= 4 if I understand the code correctly.
Yes, you are right. Thanks.
Jiri, this patch is a prerequisite for "[PATCH 10/14] HID: i2c-hid: reorder allocation/free of buffers". could you please what for a v2 before applying 10/14?
Cheers, Benjamin
> >> dev_err(&client->dev, "weird size of HID descriptor (%u)\n", >> dsize); >> return -ENODEV; > > > -- > Jean Delvare
| |