On Wed, 2018-05-02 at 23:18 +0530, Amit Pundir wrote:
> From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
>
> Possible buffer overflow when reading next_read_size bytes into
> tmp buffer after next_read_size was extracted from a previous packet.
>
> Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
> ---
> v2:
> Remove redundant __func__ from dev_dgb().
>
> drivers/nfc/fdp/i2c.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/nfc/fdp/i2c.c b/drivers/nfc/fdp/i2c.c
> index c4da50e..b80d1ad 100644
> --- a/drivers/nfc/fdp/i2c.c
> +++ b/drivers/nfc/fdp/i2c.c
> @@ -176,6 +176,15 @@ static int fdp_nci_i2c_read(struct fdp_i2c_phy
> *phy, struct sk_buff **skb)
> /* Packet that contains a length */
> if (tmp[0] == 0 && tmp[1] == 0) {
> phy->next_read_size = (tmp[2] << 8) + tmp[3]
> + 3;
> + /*
> + * Ensure next_read_size does not exceed
> sizeof(tmp)
> + * for reading that many bytes during next
> iteration
> + */
> + if (phy->next_read_size >
> FDP_NCI_I2C_MAX_PAYLOAD) {
> + dev_dbg(&client->dev, "corrupted
> packet\n");
> + phy->next_read_size = 5;
Shouldn't be this magic replaced by
phy->next_read_size = FDP_NCI_I2C_MIN_PAYLOAD;
?
> + goto flush;
> + }
> } else {
> phy->next_read_size =
> FDP_NCI_I2C_MIN_PAYLOAD;
>
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
