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authorSamuel Ortiz <sameo@linux.intel.com>2012-12-07 16:37:30 +0100
committerSamuel Ortiz <sameo@linux.intel.com>2013-01-10 00:48:25 +0100
commit1727cf937401945a590ebf25c7fa65a4853fe9bb (patch)
tree481c0ec5c71347d2e4cded197d106e31b4b53c25 /net/nfc
parent2593c2c6ec236c6aedbb8182d103185ab6580285 (diff)
downloadlinux-1727cf937401945a590ebf25c7fa65a4853fe9bb.tar.gz
NFC: llcp: Fix Rx memory leak
The reference count bump on the llcp Rx path is leading to a memory leak whenever we're not receiving an I frame. We fix that by removing the refcount bump (drivers must not free their received skb) and using it only in the I frame path, when the frame is actually queued. In that case, the skb will only be freed when someone fetches it from userspace. in all other cases, LLCP received frames will be freed when leaving the Rx work queue. Reported-by: Eric Lapuyade <eric.lapuyade@linux.intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'net/nfc')
-rw-r--r--net/nfc/llcp/llcp.c35
1 files changed, 25 insertions, 10 deletions
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index 003c82fe8bd..85bc75c38de 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -782,8 +782,14 @@ static void nfc_llcp_recv_ui(struct nfc_llcp_local *local,
/* There is no sequence with UI frames */
skb_pull(skb, LLCP_HEADER_SIZE);
- if (sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
- pr_err("receive queue is full\n");
+ if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
+ /*
+ * UI frames will be freed from the socket layer, so we
+ * need to keep them alive until someone receives them.
+ */
+ skb_get(skb);
+ } else {
+ pr_err("Receive queue is full\n");
kfree_skb(skb);
}
@@ -977,8 +983,14 @@ static void nfc_llcp_recv_hdlc(struct nfc_llcp_local *local,
pr_err("Received out of sequence I PDU\n");
skb_pull(skb, LLCP_HEADER_SIZE + LLCP_SEQUENCE_SIZE);
- if (sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
- pr_err("receive queue is full\n");
+ if (!sock_queue_rcv_skb(&llcp_sock->sk, skb)) {
+ /*
+ * I frames will be freed from the socket layer, so we
+ * need to keep them alive until someone receives them.
+ */
+ skb_get(skb);
+ } else {
+ pr_err("Receive queue is full\n");
kfree_skb(skb);
}
}
@@ -1299,6 +1311,13 @@ static void nfc_llcp_rx_work(struct work_struct *work)
local->rx_pending = NULL;
}
+static void __nfc_llcp_recv(struct nfc_llcp_local *local, struct sk_buff *skb)
+{
+ local->rx_pending = skb;
+ del_timer(&local->link_timer);
+ schedule_work(&local->rx_work);
+}
+
void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
{
struct nfc_llcp_local *local = (struct nfc_llcp_local *) data;
@@ -1309,9 +1328,7 @@ void nfc_llcp_recv(void *data, struct sk_buff *skb, int err)
return;
}
- local->rx_pending = skb_get(skb);
- del_timer(&local->link_timer);
- schedule_work(&local->rx_work);
+ __nfc_llcp_recv(local, skb);
}
int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
@@ -1322,9 +1339,7 @@ int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb)
if (local == NULL)
return -ENODEV;
- local->rx_pending = skb_get(skb);
- del_timer(&local->link_timer);
- schedule_work(&local->rx_work);
+ __nfc_llcp_recv(local, skb);
return 0;
}