3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpen...@oracle.com>

commit d07f1e8600ccb885c8f4143402b8912f7d827bcb upstream.

Smatch says that skb->data is untrusted so we need to check to make sure
that the memcpy() doesn't overflow.

Fixes: cfad1ba87150 ('NFC: Initial support for Inside Secure microread')
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
Signed-off-by: Samuel Ortiz <sa...@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/nfc/microread/microread.c |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

--- a/drivers/nfc/microread/microread.c
+++ b/drivers/nfc/microread/microread.c
@@ -501,9 +501,13 @@ static void microread_target_discovered(
                targets->sens_res =
                         be16_to_cpu(*(u16 *)&skb->data[MICROREAD_EMCF_A_ATQA]);
                targets->sel_res = skb->data[MICROREAD_EMCF_A_SAK];
-               memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_A_UID],
-                      skb->data[MICROREAD_EMCF_A_LEN]);
                targets->nfcid1_len = skb->data[MICROREAD_EMCF_A_LEN];
+               if (targets->nfcid1_len > sizeof(targets->nfcid1)) {
+                       r = -EINVAL;
+                       goto exit_free;
+               }
+               memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_A_UID],
+                      targets->nfcid1_len);
                break;
        case MICROREAD_GATE_ID_MREAD_ISO_A_3:
                targets->supported_protocols =
@@ -511,9 +515,13 @@ static void microread_target_discovered(
                targets->sens_res =
                         be16_to_cpu(*(u16 
*)&skb->data[MICROREAD_EMCF_A3_ATQA]);
                targets->sel_res = skb->data[MICROREAD_EMCF_A3_SAK];
-               memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_A3_UID],
-                      skb->data[MICROREAD_EMCF_A3_LEN]);
                targets->nfcid1_len = skb->data[MICROREAD_EMCF_A3_LEN];
+               if (targets->nfcid1_len > sizeof(targets->nfcid1)) {
+                       r = -EINVAL;
+                       goto exit_free;
+               }
+               memcpy(targets->nfcid1, &skb->data[MICROREAD_EMCF_A3_UID],
+                      targets->nfcid1_len);
                break;
        case MICROREAD_GATE_ID_MREAD_ISO_B:
                targets->supported_protocols = NFC_PROTO_ISO14443_B_MASK;


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