NFC: st21nfca: Add condition to make sure atr_req->length is valid.
NFC: st21nfca: Add condition to make sure atr_req->length is valid.

gb_len in st21nfca_tm_send_atr_res can be negative. Not checking for
that could lead to a potential kernel oops.
We now make sure that atr_req->length > sizeof(struct st21nfca_atr_req)
to avoid such situation.

Signed-off-by: Christophe Ricard <7fc2cd33e78f60c767c0b054f476a876f109b675@st.com>
Signed-off-by: Samuel Ortiz <0ba86cb3f08bbb861958e54bd3438887adb4263c@linux.intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs