[PATCH net-next 22/23] rxrpc: Make the parsing of xdr payloads more coherent

[David Howells]

Make the parsing of xdr-encoded payloads, as passed to add_key, more
coherent.  Shuttling back and forth between various variables was a bit
hard to follow.

Signed-off-by: David Howells <dhowe...@redhat.com>
---

 net/rxrpc/key.c |   16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index c08827b87979..19b730b58516 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -135,7 +135,7 @@ static int rxrpc_preparse_xdr_rxkad(struct 
key_preparsed_payload *prep,
  */
 static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
 {
-       const __be32 *xdr = prep->data, *token;
+       const __be32 *xdr = prep->data, *p;
        const char *cp;
        unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix;
        size_t datalen = prep->datalen;
@@ -189,20 +189,20 @@ static int rxrpc_preparse_xdr(struct 
key_preparsed_payload *prep)
                goto not_xdr;
 
        /* check each token wrapper */
-       token = xdr;
+       p = xdr;
        loop = ntoken;
        do {
                if (datalen < 8)
                        goto not_xdr;
-               toklen = ntohl(*xdr++);
-               sec_ix = ntohl(*xdr);
+               toklen = ntohl(*p++);
+               sec_ix = ntohl(*p);
                datalen -= 4;
                _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
                paddedlen = (toklen + 3) & ~3;
                if (toklen < 20 || toklen > datalen || paddedlen > datalen)
                        goto not_xdr;
                datalen -= paddedlen;
-               xdr += paddedlen >> 2;
+               p += paddedlen >> 2;
 
        } while (--loop > 0);
 
@@ -214,13 +214,11 @@ static int rxrpc_preparse_xdr(struct 
key_preparsed_payload *prep)
         * - we ignore the cellname, relying on the key to be correctly named
         */
        do {
-               xdr = token;
                toklen = ntohl(*xdr++);
-               token = xdr + ((toklen + 3) >> 2);
                sec_ix = ntohl(*xdr++);
                toklen -= 4;
 
-               _debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
+               _debug("TOKEN type=%x len=%x", sec_ix, toklen);
 
                switch (sec_ix) {
                case RXRPC_SECURITY_RXKAD:
@@ -234,6 +232,8 @@ static int rxrpc_preparse_xdr(struct key_preparsed_payload 
*prep)
                        goto error;
                }
 
+               xdr += (toklen + 3) / 4;
+
        } while (--ntoken > 0);
 
        _leave(" = 0");