Re: Patch "lockd: fix decoding of TEST results" has been added to the 4.4-stable tree

[Greg KH <greg@kroah.com>]

On Fri, Dec 06, 2019 at 04:24:54PM -0500, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
> 
>     lockd: fix decoding of TEST results
> 
> to the 4.4-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      lockd-fix-decoding-of-test-results.patch
> and it can be found in the queue-4.4 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
> 
> 
> 
> commit 66c45912a1133ed5483e1559bad8a5d6bd2f4275
> Author: J. Bruce Fields <bfields@redhat.com>
> Date:   Mon Nov 26 11:36:52 2018 -0500
> 
>     lockd: fix decoding of TEST results
>     
>     [ Upstream commit b8db159239b3f51e2b909859935cc25cb3ff3eed ]
>     
>     We fail to advance the read pointer when reading the stat.oh field that
>     identifies the lock-holder in a TEST result.
>     
>     This turns out not to matter if the server is knfsd, which always
>     returns a zero-length field.  But other servers (Ganesha is an example)
>     may not do this.  The result is bad values in fcntl F_GETLK results.
>     
>     Fix this.
>     
>     Signed-off-by: J. Bruce Fields <bfields@redhat.com>
>     Signed-off-by: Sasha Levin <sashal@kernel.org>
> 
> diff --git a/fs/lockd/clnt4xdr.c b/fs/lockd/clnt4xdr.c
> index d3e40db289302..4fdf8dae0db28 100644
> --- a/fs/lockd/clnt4xdr.c
> +++ b/fs/lockd/clnt4xdr.c
> @@ -127,24 +127,14 @@ static void encode_netobj(struct xdr_stream *xdr,
>  static int decode_netobj(struct xdr_stream *xdr,
>  			 struct xdr_netobj *obj)
>  {
> -	u32 length;
> -	__be32 *p;
> +	ssize_t ret;
>  
> -	p = xdr_inline_decode(xdr, 4);
> -	if (unlikely(p == NULL))
> -		goto out_overflow;
> -	length = be32_to_cpup(p++);
> -	if (unlikely(length > XDR_MAX_NETOBJ))
> -		goto out_size;
> -	obj->len = length;
> -	obj->data = (u8 *)p;
> +	ret = xdr_stream_decode_opaque_inline(xdr, (void *)&obj->data,
> +						XDR_MAX_NETOBJ);
> +	if (unlikely(ret < 0))
> +		return -EIO;
> +	obj->len = ret;
>  	return 0;
> -out_size:
> -	dprintk("NFS: returned netobj was too long: %u\n", length);
> -	return -EIO;
> -out_overflow:
> -	print_overflow_msg(__func__, xdr);
> -	return -EIO;
>  }
>  
>  /*
> diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
> index 3e9f7874b9755..29392d66473c8 100644
> --- a/fs/lockd/clntxdr.c
> +++ b/fs/lockd/clntxdr.c
> @@ -124,24 +124,14 @@ static void encode_netobj(struct xdr_stream *xdr,
>  static int decode_netobj(struct xdr_stream *xdr,
>  			 struct xdr_netobj *obj)
>  {
> -	u32 length;
> -	__be32 *p;
> +	ssize_t ret;
>  
> -	p = xdr_inline_decode(xdr, 4);
> -	if (unlikely(p == NULL))
> -		goto out_overflow;
> -	length = be32_to_cpup(p++);
> -	if (unlikely(length > XDR_MAX_NETOBJ))
> -		goto out_size;
> -	obj->len = length;
> -	obj->data = (u8 *)p;
> +	ret = xdr_stream_decode_opaque_inline(xdr, (void *)&obj->data,
> +			XDR_MAX_NETOBJ);
> +	if (unlikely(ret < 0))
> +		return -EIO;
> +	obj->len = ret;
>  	return 0;
> -out_size:
> -	dprintk("NFS: returned netobj was too long: %u\n", length);
> -	return -EIO;
> -out_overflow:
> -	print_overflow_msg(__func__, xdr);
> -	return -EIO;
>  }
>  
>  /*

Breaks the build on 4.4, so I'm dropping it from there :(