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Subject: Re: [PATCH] SUNRPC: Fix xdr_encode_bool()
From:   Jeff Layton <jlayton@kernel.org>
To:     Chuck Lever <chuck.lever@oracle.com>, linux-nfs@vger.kernel.org
Date:   Tue, 19 Jul 2022 11:49:44 -0400
In-Reply-To: <165823671509.3047.16569036635528856192.stgit@manet.1015granger.net>
References: <165823671509.3047.16569036635528856192.stgit@manet.1015granger.net>
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On Tue, 2022-07-19 at 09:18 -0400, Chuck Lever wrote:
> I discovered that xdr_encode_bool() was returning the same address
> that was passed in the @p parameter. The documenting comment states
> that the intent is to return the address of the next buffer
> location, just like the other "xdr_encode_*" helpers.
>=20
> The result was the encoded results of NFSv3 PATHCONF operations were
> not formed correctly.
>=20
> Fixes: ded04a587f6c ("NFSD: Update the NFSv3 PATHCONF3res encoder to use =
struct xdr_stream")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
>  include/linux/sunrpc/xdr.h |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>=20
> diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
> index 5860f32e3958..986c8a17ca5e 100644
> --- a/include/linux/sunrpc/xdr.h
> +++ b/include/linux/sunrpc/xdr.h
> @@ -419,8 +419,8 @@ static inline int xdr_stream_encode_item_absent(struc=
t xdr_stream *xdr)
>   */
>  static inline __be32 *xdr_encode_bool(__be32 *p, u32 n)
>  {
> -	*p =3D n ? xdr_one : xdr_zero;
> -	return p++;
> +	*p++ =3D n ? xdr_one : xdr_zero;
> +	return p;
>  }
> =20
>  /**
>=20
>=20

Nice catch. Postincrement operators strike again!

Reviewed-by: Jeff Layton <jlayton@kernel.org>