Re: [PATCH V2] [nfs/nfs-utils/libtirpc] clnt_raw.c: fix a possible null pointer dereference

[Steve Dickson <steved@xxxxxxxxxx>]

On 10/28/22 5:10 AM, Zhi Li wrote:
> Since clntraw_private could be dereferenced before
> allocated, protect it by checking its value in advance.
>
> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2138317
> Signed-off-by: Zhi Li <yieli@xxxxxxxxxx>
Committed...

steved.
> ---
>   src/clnt_raw.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/src/clnt_raw.c b/src/clnt_raw.c
> index 31f9d0c..03f839d 100644
> --- a/src/clnt_raw.c
> +++ b/src/clnt_raw.c
> @@ -142,7 +142,7 @@ clnt_raw_call(h, proc, xargs, argsp, xresults, resultsp, timeout)
>   	struct timeval timeout;
>   {
>   	struct clntraw_private *clp = clntraw_private;
> -	XDR *xdrs = &clp->xdr_stream;
> +	XDR *xdrs;
>   	struct rpc_msg msg;
>   	enum clnt_stat status;
>   	struct rpc_err error;
> @@ -154,6 +154,7 @@ clnt_raw_call(h, proc, xargs, argsp, xresults, resultsp, timeout)
>   		mutex_unlock(&clntraw_lock);
>   		return (RPC_FAILED);
>   	}
> +	xdrs = &clp->xdr_stream;
>   	mutex_unlock(&clntraw_lock);
>   
>   call_again:
> @@ -245,7 +246,7 @@ clnt_raw_freeres(cl, xdr_res, res_ptr)
>   	void *res_ptr;
>   {
>   	struct clntraw_private *clp = clntraw_private;
> -	XDR *xdrs = &clp->xdr_stream;
> +	XDR *xdrs;
>   	bool_t rval;
>   
>   	mutex_lock(&clntraw_lock);
> @@ -254,6 +255,7 @@ clnt_raw_freeres(cl, xdr_res, res_ptr)
>   		mutex_unlock(&clntraw_lock);
>   		return (rval);
>   	}
> +	xdrs = &clp->xdr_stream;
>   	mutex_unlock(&clntraw_lock);
>   	xdrs->x_op = XDR_FREE;
>   	return ((*xdr_res)(xdrs, res_ptr));