Merge branch 'nfc-skb-leaks'

Shang XiaoJing says:

====================
nfc: Fix potential memory leak of skb

There are 6 kinds of send functions can be called by nci_send_frame():
	virtual_nci_send(),
	fdp_nci_send(),
	nxp_nci_send(),
	s3fwrn5_nci_send(),
	nfcmrvl_nci_send(),
	st_nci_send();

1. virtual_nci_send() will memleak the skb, and has been fixed before.

2. fdp_nci_send() won't free the skb no matter whether write() succeed.

3-4. nxp_nci_send() and s3fwrn5_nci_send() will only free the skb when
write() failed, however write() will not free the skb by itself for when
succeeds.

5. nfcmrvl_nci_send() will call nfcmrvl_XXX_nci_send(), where some of
them will free the skb, but nfcmrvl_i2c_nci_send() only free the skb
when i2c_master_send() return >=0, and memleak will happen when
i2c_master_send() failed in nfcmrvl_i2c_nci_send().

6. st_nci_send() will queue the skb into other list and finally be
freed.

Fix the potential memory leak of skb.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/nfc/fdp/fdp.c

@@ -249,11 +249,19 @@ static int fdp_nci_close(struct nci_dev *ndev)
 static int fdp_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
 {
 	struct fdp_nci_info *info = nci_get_drvdata(ndev);
+	int ret;
 
 	if (atomic_dec_and_test(&info->data_pkt_counter))
 		info->data_pkt_counter_cb(ndev);
 
-	return info->phy_ops->write(info->phy, skb);
+	ret = info->phy_ops->write(info->phy, skb);
+	if (ret < 0) {
+		kfree_skb(skb);
+		return ret;
+	}
+
+	consume_skb(skb);
+	return 0;
 }
 
 static int fdp_nci_request_firmware(struct nci_dev *ndev)

drivers/nfc/nfcmrvl/i2c.c

@@ -132,10 +132,15 @@ static int nfcmrvl_i2c_nci_send(struct nfcmrvl_private *priv,
 			ret = -EREMOTEIO;
 		} else
 			ret = 0;
-		kfree_skb(skb);
 	}
 
-	return ret;
+	if (ret) {
+		kfree_skb(skb);
+		return ret;
+	}
+
+	consume_skb(skb);
+	return 0;
 }
 
 static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv,

drivers/nfc/nxp-nci/core.c

@@ -80,10 +80,13 @@ static int nxp_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
 		return -EINVAL;
 
 	r = info->phy_ops->write(info->phy_id, skb);
-	if (r < 0)
+	if (r < 0) {
 		kfree_skb(skb);
+		return r;
+	}
 
-	return r;
+	consume_skb(skb);
+	return 0;
 }
 
 static int nxp_nci_rf_pll_unlocked_ntf(struct nci_dev *ndev,

drivers/nfc/s3fwrn5/core.c

@@ -110,11 +110,15 @@ static int s3fwrn5_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
 	}
 
 	ret = s3fwrn5_write(info, skb);
-	if (ret < 0)
+	if (ret < 0) {
 		kfree_skb(skb);
+		mutex_unlock(&info->mutex);
+		return ret;
+	}
 
+	consume_skb(skb);
 	mutex_unlock(&info->mutex);
-	return ret;
+	return 0;
 }
 
 static int s3fwrn5_nci_post_setup(struct nci_dev *ndev)