re: SUNRPC: Add RPC based upcall mechanism for RPCGSS auth

[Dan Carpenter <dan.carpenter@oracle.com>]

Hello Simo Sorce,

The patch 1d658336b05f: "SUNRPC: Add RPC based upcall mechanism for 
RPCGSS auth" from May 25, 2012, leads to the following warning:
"net/sunrpc/auth_gss/gss_rpc_xdr.c:30 gssx_check_pointer()
	 warn: signedness bug returning '(-28)'"

net/sunrpc/auth_gss/gss_rpc_xdr.c
    24  static bool gssx_check_pointer(struct xdr_stream *xdr)
    25  {
    26          __be32 *p;
    27  
    28          p = xdr_reserve_space(xdr, 4);
    29          if (unlikely(p == NULL))
    30                  return -ENOSPC;
                               ^^^^^^^
This is casted implicitly to "true".  Functions named "check" are a bad
idea anyways because it's not clear what the return value will be.  It's
better to use "gssx_pointer_ok()" or "valid" where obviously true means
that the pointer is ok.

    31          return *p?true:false;

We just reserved "*p" so doesn't this point to uninitialized data?  It
points to a __be32.  So we're not really checking a pointer we're
checking that __be32 is non-zero.

    32  }

regards,
dan carpenter