Commit 06b332a5 authored by J. Bruce Fields's avatar J. Bruce Fields
Browse files

nfsd4: check backchannel attributes on create_session 



Make sure the client gives us an adequate backchannel.

Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent 55c760cf

fs/nfsd/nfs4callback.c

+1 −24
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ 
#include "nfsd.h"

#include "state.h"

#include "netns.h"

#include "xdr4cb.h"



#define NFSDDBG_FACILITY                NFSDDBG_PROC
@@ -53,30 +54,6 @@ enum { 
	NFSPROC4_CLNT_CB_SEQUENCE,

};



#define NFS4_MAXTAGLEN		20



#define NFS4_enc_cb_null_sz		0

#define NFS4_dec_cb_null_sz		0

#define cb_compound_enc_hdr_sz		4

#define cb_compound_dec_hdr_sz		(3 + (NFS4_MAXTAGLEN >> 2))

#define sessionid_sz			(NFS4_MAX_SESSIONID_LEN >> 2)

#define cb_sequence_enc_sz		(sessionid_sz + 4 +             \

					1 /* no referring calls list yet */)

#define cb_sequence_dec_sz		(op_dec_sz + sessionid_sz + 4)



#define op_enc_sz			1

#define op_dec_sz			2

#define enc_nfs4_fh_sz			(1 + (NFS4_FHSIZE >> 2))

#define enc_stateid_sz			(NFS4_STATEID_SIZE >> 2)

#define NFS4_enc_cb_recall_sz		(cb_compound_enc_hdr_sz +       \

					cb_sequence_enc_sz +            \

					1 + enc_stateid_sz +            \

					enc_nfs4_fh_sz)



#define NFS4_dec_cb_recall_sz		(cb_compound_dec_hdr_sz  +      \

					cb_sequence_dec_sz +            \

					op_dec_sz)



struct nfs4_cb_compound_hdr {

	/* args */

	u32		ident;	/* minorversion 0 only */

fs/nfsd/nfs4state.c

+25 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ 
#include <linux/sunrpc/svcauth_gss.h>

#include <linux/sunrpc/addr.h>

#include "xdr4.h"

#include "xdr4cb.h"

#include "vfs.h"

#include "current_stateid.h"
@@ -1794,6 +1795,27 @@ static __be32 check_forechannel_attrs(struct nfsd4_channel_attrs *ca, struct nfs 
	return nfs_ok;

}



static __be32 check_backchannel_attrs(struct nfsd4_channel_attrs *ca)

{

	ca->headerpadsz = 0;



	/*

	 * These RPC_MAX_HEADER macros are overkill, especially since we

	 * don't even do gss on the backchannel yet.  But this is still

	 * less than 1k.  Tighten up this estimate in the unlikely event

	 * it turns out to be a problem for some client:

	 */

	if (ca->maxreq_sz < NFS4_enc_cb_recall_sz + RPC_MAX_HEADER_WITH_AUTH)

		return nfserr_toosmall;

	if (ca->maxresp_sz < NFS4_dec_cb_recall_sz + RPC_MAX_REPHEADER_WITH_AUTH)

		return nfserr_toosmall;

	ca->maxresp_cached = 0;

	if (ca->maxops < 2)

		return nfserr_toosmall;



	return nfs_ok;

}



__be32

nfsd4_create_session(struct svc_rqst *rqstp,

		     struct nfsd4_compound_state *cstate,
@@ -1810,6 +1832,9 @@ nfsd4_create_session(struct svc_rqst *rqstp, 
	if (cr_ses->flags & ~SESSION4_FLAG_MASK_A)

		return nfserr_inval;

	status = check_forechannel_attrs(&cr_ses->fore_channel, nn);

	if (status)

		return status;

	status = check_backchannel_attrs(&cr_ses->back_channel);

	if (status)

		return status;

	status = nfserr_jukebox;

fs/nfsd/xdr4cb.h

0 → 100644
+23 −0
Original line number Diff line number Diff line 
#define NFS4_MAXTAGLEN		20



#define NFS4_enc_cb_null_sz		0

#define NFS4_dec_cb_null_sz		0

#define cb_compound_enc_hdr_sz		4

#define cb_compound_dec_hdr_sz		(3 + (NFS4_MAXTAGLEN >> 2))

#define sessionid_sz			(NFS4_MAX_SESSIONID_LEN >> 2)

#define cb_sequence_enc_sz		(sessionid_sz + 4 +             \

					1 /* no referring calls list yet */)

#define cb_sequence_dec_sz		(op_dec_sz + sessionid_sz + 4)



#define op_enc_sz			1

#define op_dec_sz			2

#define enc_nfs4_fh_sz			(1 + (NFS4_FHSIZE >> 2))

#define enc_stateid_sz			(NFS4_STATEID_SIZE >> 2)

#define NFS4_enc_cb_recall_sz		(cb_compound_enc_hdr_sz +       \

					cb_sequence_enc_sz +            \

					1 + enc_stateid_sz +            \

					enc_nfs4_fh_sz)



#define NFS4_dec_cb_recall_sz		(cb_compound_dec_hdr_sz  +      \

					cb_sequence_dec_sz +            \

					op_dec_sz)

include/linux/sunrpc/msg_prot.h

+3 −0
Original line number Diff line number Diff line
@@ -138,6 +138,9 @@ typedef __be32 rpc_fraghdr; 
#define RPC_MAX_HEADER_WITH_AUTH \

	(RPC_CALLHDRSIZE + 2*(2+RPC_MAX_AUTH_SIZE/4))



#define RPC_MAX_REPHEADER_WITH_AUTH \

	(RPC_REPHDRSIZE + (2 + RPC_MAX_AUTH_SIZE/4))



/*

 * RFC1833/RFC3530 rpcbind (v3+) well-known netid's.

 */