Re: [PATCH net v2] net: qrtr: fix endian handling of confirm_rx field

[Manivannan Sadhasivam]

On Tue, Mar 24, 2026 at 08:50:33AM +0100, Alexander Wilhelm wrote:
> Convert confirm_rx to little endian when enqueueing and convert it back on
> receive. This fixes control flow on big endian hosts, little endian is
> unaffected.
> 
> On transmit, store confirm_rx as __le32 using cpu_to_le32(). On receive,
> apply le32_to_cpu() before using the value. !! ensures the value is 0 or 1
> in native endianness, so the conversion isn’t strictly required here, but
> it is kept for consistency and clarity.
> 
> Fixes: 5fdeb0d372ab ("net: qrtr: Implement outgoing flow control")
> Signed-off-by: Alexander Wilhelm <alexander.wilhelm@xxxxxxxxxxxx>

Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>

- Mani

> ---
> Changes in v2:
> - Rebase on latest net tree
> - Improve commit message
> - Link to v1: https://lore.kernel.org/r/20260320-qrtr-fix-confirm_rx-on-big-endian-v1-1-e1a337dc1a38@xxxxxxxxxxxx
> ---
>  net/qrtr/af_qrtr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/net/qrtr/af_qrtr.c b/net/qrtr/af_qrtr.c
> index 55fd2dd37588..bea1f1720e7f 100644
> --- a/net/qrtr/af_qrtr.c
> +++ b/net/qrtr/af_qrtr.c
> @@ -365,7 +365,7 @@ static int qrtr_node_enqueue(struct qrtr_node *node, struct sk_buff *skb,
>  	}
>  
>  	hdr->size = cpu_to_le32(len);
> -	hdr->confirm_rx = !!confirm_rx;
> +	hdr->confirm_rx = cpu_to_le32(!!confirm_rx);
>  
>  	rc = skb_put_padto(skb, ALIGN(len, 4) + sizeof(*hdr));
>  
> @@ -466,7 +466,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
>  		cb->type = le32_to_cpu(v1->type);
>  		cb->src_node = le32_to_cpu(v1->src_node_id);
>  		cb->src_port = le32_to_cpu(v1->src_port_id);
> -		cb->confirm_rx = !!v1->confirm_rx;
> +		cb->confirm_rx = !!le32_to_cpu(v1->confirm_rx);
>  		cb->dst_node = le32_to_cpu(v1->dst_node_id);
>  		cb->dst_port = le32_to_cpu(v1->dst_port_id);
>  
> 
> ---
> base-commit: 70b439bf06f6a12e491f827fa81a9887a11501f9
> change-id: 20260324-b4-qrtr-fix-confirm_rx-on-big-endian-ee2b9637d265
> 
> Best regards,
> -- 
> Alexander Wilhelm <alexander.wilhelm@xxxxxxxxxxxx>
> 

-- 
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