On Thu, Jan 05, 2017 at 10:17:45AM -0800, Guenter Roeck wrote:
> The following crash may be seen if bad data is received from the
> touchscreen.
>
> [ 2189.425150] elants_i2c i2c-ELAN0001:00: unknown packet ff ff ff ff
> [ 2189.430738] divide error: 0000 [#1] PREEMPT SMP
...
>
> The problem was seen with a 3.18 based kernel, but there is no reason
> to believe that the upstream code is safe.
>
> Signed-off-by: Guenter Roeck <[email protected]>
Applied and marked for stable, thank you.
> ---
> drivers/input/touchscreen/elants_i2c.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/touchscreen/elants_i2c.c
> b/drivers/input/touchscreen/elants_i2c.c
> index 02aec284deca..3e6003d32e56 100644
> --- a/drivers/input/touchscreen/elants_i2c.c
> +++ b/drivers/input/touchscreen/elants_i2c.c
> @@ -914,9 +914,9 @@ static irqreturn_t elants_i2c_irq(int irq, void *_dev)
>
> case QUEUE_HEADER_NORMAL:
> report_count = ts->buf[FW_HDR_COUNT];
> - if (report_count > 3) {
> + if (report_count == 0 || report_count > 3) {
> dev_err(&client->dev,
> - "too large report count: %*ph\n",
> + "bad report count: %*ph\n",
> HEADER_SIZE, ts->buf);
> break;
> }
> --
> 2.7.4
>
--
Dmitry
