[PATCH v2] fs: nfs: Error if a port is unregistered

[Sascha Hauer]

On Thu, Feb 02, 2023 at 10:20:24PM +1100, John Watts wrote:
> If a server doesn't provide a service the port lookup will return 0.
> 
> Check for this, return an appropriate error code and give a hint as to
> why this might be happening.
> 
> This was tested by running NFS with UDP disabled, which seems to be
> the default in Arch at least.
> 
> Signed-off-by: John Watts <contact at jookia.org>
> ---
> Changes v1 -> v2:
> - Added error message
> ---
>  fs/nfs.c | 6 ++++++
>  1 file changed, 6 insertions(+)

Applied, thanks

Sascha

> 
> diff --git a/fs/nfs.c b/fs/nfs.c
> index 446d0f7946..1a0b28442d 100644
> --- a/fs/nfs.c
> +++ b/fs/nfs.c
> @@ -571,6 +571,12 @@ static int rpc_lookup_req(struct nfs_priv *npriv, uint32_t prog, uint32_t ver)
>  
>  	nfs_free_packet(nfs_packet);
>  
> +	if (port == 0) {
> +		pr_warn("No UDP port for RPC program %i! "
> +		        "Is your NFS server TCP only?\n", prog);
> +		return -ENOENT;
> +	}
> +
>  	return port;
>  }
>  
> -- 
> 2.39.1
> 
> 
> 

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