From: Mark Greer <mgreer@animalcreek.com>
Date: Thu, 15 Jun 2017 17:46:15 +0000 (-0700)
Subject: NFC: digital: NFC-A SEL_RES must be one byte
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=7f9f171336baec8ec71d57b6d329bf8cea5c1562;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

NFC: digital: NFC-A SEL_RES must be one byte

Section 4.8.2 (SEL_RES Response) of NFC Forum's NFC Digital Protocol
Technical Specification dated 2010-11-17 clearly states that the size
of a SEL_RES Response is one byte.  Enforce this restriction in the
code.

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
---

diff --git a/net/nfc/digital_technology.c b/net/nfc/digital_technology.c
index 3cc3448da524..2021d1d58a75 100644
--- a/net/nfc/digital_technology.c
+++ b/net/nfc/digital_technology.c
@@ -27,6 +27,7 @@
 
 #define DIGITAL_SDD_RES_CT  0x88
 #define DIGITAL_SDD_RES_LEN 5
+#define DIGITAL_SEL_RES_LEN 1
 
 #define DIGITAL_SEL_RES_NFCID1_COMPLETE(sel_res) (!((sel_res) & 0x04))
 #define DIGITAL_SEL_RES_IS_T2T(sel_res) (!((sel_res) & 0x60))
@@ -299,7 +300,7 @@ static void digital_in_recv_sel_res(struct nfc_digital_dev *ddev, void *arg,
 		}
 	}
 
-	if (!resp->len) {
+	if (resp->len != DIGITAL_SEL_RES_LEN) {
 		rc = -EIO;
 		goto exit;
 	}