Within the monitor functionality, the global atomic variable called
monitor_promisc ensures that no memory allocation happend when there
is actually no client listening. This means it is safe to just create
a copy of the skb since it is guaranteed that at least one client
exists. No extra checks needed.
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
---
net/bluetooth/hci_sock.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index e176a988625e..026e84a80659 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -221,6 +221,7 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb)
{
struct sock *sk;
struct sk_buff *skb_copy = NULL;
+ struct hci_mon_hdr *hdr;
__le16 opcode;
if (!atomic_read(&monitor_promisc))
@@ -251,6 +252,17 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb)
return;
}
+ /* Create a private copy with headroom */
+ skb_copy = __pskb_copy_fclone(skb, HCI_MON_HDR_SIZE, GFP_ATOMIC, true);
+ if (!skb_copy)
+ return;
+
+ /* Put header before the data */
+ hdr = (void *) skb_push(skb_copy, HCI_MON_HDR_SIZE);
+ hdr->opcode = opcode;
+ hdr->index = cpu_to_le16(hdev->id);
+ hdr->len = cpu_to_le16(skb->len);
+
read_lock(&hci_sk_list.lock);
sk_for_each(sk, &hci_sk_list.head) {
@@ -262,22 +274,6 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb)
if (hci_pi(sk)->channel != HCI_CHANNEL_MONITOR)
continue;
- if (!skb_copy) {
- struct hci_mon_hdr *hdr;
-
- /* Create a private copy with headroom */
- skb_copy = __pskb_copy_fclone(skb, HCI_MON_HDR_SIZE,
- GFP_ATOMIC, true);
- if (!skb_copy)
- continue;
-
- /* Put header before the data */
- hdr = (void *) skb_push(skb_copy, HCI_MON_HDR_SIZE);
- hdr->opcode = opcode;
- hdr->index = cpu_to_le16(hdev->id);
- hdr->len = cpu_to_le16(skb->len);
- }
-
nskb = skb_clone(skb_copy, GFP_ATOMIC);
if (!nskb)
continue;
--
2.1.0
--
To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
