On 9/17/2024 10:25 AM, Youssef Samir wrote:
Hi Chris,
On 9/17/2024 3:59 PM, Chris Lew wrote:
Hi Youssef,
On 9/16/2024 10:08 AM, Youssef Samir wrote:
When broadcasting data to multiple nodes via MHI, using skb_clone()
causes all nodes to receive the same header data. This can result in
packets being discarded by endpoints, leading to lost data.
This issue occurs when a socket is closed, and a QRTR_TYPE_DEL_CLIENT
packet is broadcasted. All nodes receive the same destination node ID,
causing the node connected to the client to discard the packet and
remain unaware of the client's deletion.
I guess this never happens for the SMD/RPMSG transport because the skb is consumed within the context of qrtr_node_enqueue where as MHI queues the skb to be transmitted later.
Does the duplicate destination node ID match the last node in the qrtr_all_nodes list?
Yes, it always matches the last node in the qrtr_all_nodes list.
Thanks for the confirmation, we haven't seen this before since most of
our platforms usually only use one MHI qrtr node.
Reviewed-by: Chris Lew <quic_clew@xxxxxxxxxxx>
Replace skb_clone() with pskb_copy(), to create a separate copy of
the header for each sk_buff.
Fixes: bdabad3e363d ("net: Add Qualcomm IPC router")
Signed-off-by: Youssef Samir <quic_yabdulra@xxxxxxxxxxx>
Reviewed-by: Jeffery Hugo <quic_jhugo@xxxxxxxxxxx>
Reviewed-by: Carl Vanderlip <quic_carlv@xxxxxxxxxxx>
---
net/qrtr/af_qrtr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/qrtr/af_qrtr.c b/net/qrtr/af_qrtr.c
index 41ece61eb57a..00c51cf693f3 100644
--- a/net/qrtr/af_qrtr.c
+++ b/net/qrtr/af_qrtr.c
@@ -884,7 +884,7 @@ static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb,
mutex_lock(&qrtr_node_lock);
list_for_each_entry(node, &qrtr_all_nodes, item) {
- skbn = skb_clone(skb, GFP_KERNEL);
+ skbn = pskb_copy(skb, GFP_KERNEL);
if (!skbn)
break;
skb_set_owner_w(skbn, skb->sk);
