Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFS: NFSv4 readdir loses entries
NFS: Micro-optimize nfs4_decode_dirent()
NFS: Fix an NFS client lockdep issue
NFS construct consistent co_ownerid for v4.1
NFS: nfs_wcc_update_inode() should set nfsi->attr_gencount
NFS improve pnfs_put_deviceid_cache debug print
NFS fix cb_sequence error processing
NFS do not find client in NFSv4 pg_authenticate
NLM: Fix "kernel BUG at fs/lockd/host.c:417!" or ".../host.c:283!"
NFS: Prevent memory allocation failure in nfsacl_encode()
NFS: nfsacl_{encode,decode} should return signed integer
NFS: Fix "kernel BUG at fs/nfs/nfs3xdr.c:1338!"
NFS: Fix "kernel BUG at fs/aio.c:554!"
NFS4: Avoid potential NULL pointer dereference in decode_and_add_ds().
NFS: fix handling of malloc failure during nfs_flush_multi()

fs/lockd/host.c

···
 					struct nsm_handle *nsm,
 					const struct nlm_reboot *info)
 {
-	struct nlm_host *host = NULL;
+	struct nlm_host *host;
 	struct hlist_head *chain;
 	struct hlist_node *pos;
 
···
 			host->h_state++;
 
 			nlm_get_host(host);
-			goto out;
+			mutex_unlock(&nlm_host_mutex);
+			return host;
 		}
 	}
-out:
+
 	mutex_unlock(&nlm_host_mutex);
-	return host;
+	return NULL;
 }
 
 /**

fs/nfs/callback.c

···
 
 #if defined(CONFIG_NFS_V4_1)
 /*
- *  * CB_SEQUENCE operations will fail until the callback sessionid is set.
- *   */
-int nfs4_set_callback_sessionid(struct nfs_client *clp)
-{
-	struct svc_serv *serv = clp->cl_rpcclient->cl_xprt->bc_serv;
-	struct nfs4_sessionid *bc_sid;
-
-	if (!serv->sv_bc_xprt)
-		return -EINVAL;
-
-	/* on success freed in xprt_free */
-	bc_sid = kmalloc(sizeof(struct nfs4_sessionid), GFP_KERNEL);
-	if (!bc_sid)
-		return -ENOMEM;
-	memcpy(bc_sid->data, &clp->cl_session->sess_id.data,
-		NFS4_MAX_SESSIONID_LEN);
-	spin_lock_bh(&serv->sv_cb_lock);
-	serv->sv_bc_xprt->xpt_bc_sid = bc_sid;
-	spin_unlock_bh(&serv->sv_cb_lock);
-	dprintk("%s set xpt_bc_sid=%u:%u:%u:%u for sv_bc_xprt %p\n", __func__,
-		((u32 *)bc_sid->data)[0], ((u32 *)bc_sid->data)[1],
-		((u32 *)bc_sid->data)[2], ((u32 *)bc_sid->data)[3],
-		serv->sv_bc_xprt);
-	return 0;
-}
-
-/*
  * The callback service for NFSv4.1 callbacks
  */
 static int
···
 		struct nfs_callback_data *cb_info)
 {
 }
-int nfs4_set_callback_sessionid(struct nfs_client *clp)
-{
-	return 0;
-}
 #endif /* CONFIG_NFS_V4_1 */
 
 /*
···
 	mutex_unlock(&nfs_callback_mutex);
 }
 
-static int check_gss_callback_principal(struct nfs_client *clp,
-					struct svc_rqst *rqstp)
+/* Boolean check of RPC_AUTH_GSS principal */
+int
+check_gss_callback_principal(struct nfs_client *clp, struct svc_rqst *rqstp)
 {
 	struct rpc_clnt *r = clp->cl_rpcclient;
 	char *p = svc_gss_principal(rqstp);
 
+	if (rqstp->rq_authop->flavour != RPC_AUTH_GSS)
+		return 1;
+
 	/* No RPC_AUTH_GSS on NFSv4.1 back channel yet */
 	if (clp->cl_minorversion != 0)
-		return SVC_DROP;
+		return 0;
 	/*
 	 * It might just be a normal user principal, in which case
 	 * userspace won't bother to tell us the name at all.
 	 */
 	if (p == NULL)
-		return SVC_DENIED;
+		return 0;
 
 	/* Expect a GSS_C_NT_HOSTBASED_NAME like "nfs@serverhostname" */
 
 	if (memcmp(p, "nfs@", 4) != 0)
-		return SVC_DENIED;
+		return 0;
 	p += 4;
 	if (strcmp(p, r->cl_server) != 0)
-		return SVC_DENIED;
-	return SVC_OK;
+		return 0;
+	return 1;
 }
 
-/* pg_authenticate method helper */
-static struct nfs_client *nfs_cb_find_client(struct svc_rqst *rqstp)
-{
-	struct nfs4_sessionid *sessionid = bc_xprt_sid(rqstp);
-	int is_cb_compound = rqstp->rq_proc == CB_COMPOUND ? 1 : 0;
-
-	dprintk("--> %s rq_proc %d\n", __func__, rqstp->rq_proc);
-	if (svc_is_backchannel(rqstp))
-		/* Sessionid (usually) set after CB_NULL ping */
-		return nfs4_find_client_sessionid(svc_addr(rqstp), sessionid,
-						  is_cb_compound);
-	else
-		/* No callback identifier in pg_authenticate */
-		return nfs4_find_client_no_ident(svc_addr(rqstp));
-}
-
-/* pg_authenticate method for nfsv4 callback threads. */
+/*
+ * pg_authenticate method for nfsv4 callback threads.
+ *
+ * The authflavor has been negotiated, so an incorrect flavor is a server
+ * bug. Drop packets with incorrect authflavor.
+ *
+ * All other checking done after NFS decoding where the nfs_client can be
+ * found in nfs4_callback_compound
+ */
 static int nfs_callback_authenticate(struct svc_rqst *rqstp)
 {
-	struct nfs_client *clp;
-	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
-	int ret = SVC_OK;
-
-	/* Don't talk to strangers */
-	clp = nfs_cb_find_client(rqstp);
-	if (clp == NULL)
-		return SVC_DROP;
-
-	dprintk("%s: %s NFSv4 callback!\n", __func__,
-			svc_print_addr(rqstp, buf, sizeof(buf)));
-
 	switch (rqstp->rq_authop->flavour) {
-		case RPC_AUTH_NULL:
-			if (rqstp->rq_proc != CB_NULL)
-				ret = SVC_DENIED;
-			break;
-		case RPC_AUTH_UNIX:
-			break;
-		case RPC_AUTH_GSS:
-			ret = check_gss_callback_principal(clp, rqstp);
-			break;
-		default:
-			ret = SVC_DENIED;
+	case RPC_AUTH_NULL:
+		if (rqstp->rq_proc != CB_NULL)
+			return SVC_DROP;
+		break;
+	case RPC_AUTH_GSS:
+		/* No RPC_AUTH_GSS support yet in NFSv4.1 */
+		 if (svc_is_backchannel(rqstp))
+			return SVC_DROP;
 	}
-	nfs_put_client(clp);
-	return ret;
+	return SVC_OK;
 }
 
 /*

fs/nfs/callback.h

···
  */
 #ifndef __LINUX_FS_NFS_CALLBACK_H
 #define __LINUX_FS_NFS_CALLBACK_H
+#include <linux/sunrpc/svc.h>
 
 #define NFS4_CALLBACK 0x40000000
 #define NFS4_CALLBACK_XDRSIZE 2048
···
 struct cb_process_state {
 	__be32			drc_status;
 	struct nfs_client	*clp;
-	struct nfs4_sessionid	*svc_sid; /* v4.1 callback service sessionid */
 };
 
 struct cb_compound_hdr_arg {
···
 extern void nfs4_check_drain_bc_complete(struct nfs4_session *ses);
 extern void nfs4_cb_take_slot(struct nfs_client *clp);
 #endif /* CONFIG_NFS_V4_1 */
-
+extern int check_gss_callback_principal(struct nfs_client *, struct svc_rqst *);
 extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
 				    struct cb_getattrres *res,
 				    struct cb_process_state *cps);

fs/nfs/callback_proc.c

···
 {
 	struct nfs_client *clp;
 	int i;
-	__be32 status;
+	__be32 status = htonl(NFS4ERR_BADSESSION);
 
 	cps->clp = NULL;
 
-	status = htonl(NFS4ERR_BADSESSION);
-	/* Incoming session must match the callback session */
-	if (memcmp(&args->csa_sessionid, cps->svc_sid, NFS4_MAX_SESSIONID_LEN))
-		goto out;
-
-	clp = nfs4_find_client_sessionid(args->csa_addr,
-					 &args->csa_sessionid, 1);
+	clp = nfs4_find_client_sessionid(args->csa_addr, &args->csa_sessionid);
 	if (clp == NULL)
 		goto out;
 
···
 	res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
 	res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
 	nfs4_cb_take_slot(clp);
-	cps->clp = clp; /* put in nfs4_callback_compound */
 
 out:
+	cps->clp = clp; /* put in nfs4_callback_compound */
 	for (i = 0; i < args->csa_nrclists; i++)
 		kfree(args->csa_rclists[i].rcl_refcalls);
 	kfree(args->csa_rclists);

fs/nfs/callback_xdr.c

···
 
 	if (hdr_arg.minorversion == 0) {
 		cps.clp = nfs4_find_client_ident(hdr_arg.cb_ident);
-		if (!cps.clp)
+		if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
 			return rpc_drop_reply;
-	} else
-		cps.svc_sid = bc_xprt_sid(rqstp);
+	}
 
 	hdr_res.taglen = hdr_arg.taglen;
 	hdr_res.tag = hdr_arg.tag;

fs/nfs/client.c

···
  * For CB_COMPOUND calls, find a client by IP address, protocol version,
  * minorversion, and sessionID
  *
- * CREATE_SESSION triggers a CB_NULL ping from servers. The callback service
- * sessionid can only be set after the CREATE_SESSION return, so a CB_NULL
- * can arrive before the callback sessionid is set. For CB_NULL calls,
- * find a client by IP address protocol version, and minorversion.
- *
  * Returns NULL if no such client
  */
 struct nfs_client *
 nfs4_find_client_sessionid(const struct sockaddr *addr,
-			   struct nfs4_sessionid *sid, int is_cb_compound)
+			   struct nfs4_sessionid *sid)
 {
 	struct nfs_client *clp;
 
···
 		if (!nfs4_has_session(clp))
 			continue;
 
-		/* Match sessionid unless cb_null call*/
-		if (is_cb_compound && (memcmp(clp->cl_session->sess_id.data,
-		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0))
+		/* Match sessionid*/
+		if (memcmp(clp->cl_session->sess_id.data,
+		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 			continue;
 
 		atomic_inc(&clp->cl_count);
···
 
 struct nfs_client *
 nfs4_find_client_sessionid(const struct sockaddr *addr,
-			   struct nfs4_sessionid *sid, int is_cb_compound)
+			   struct nfs4_sessionid *sid)
 {
 	return NULL;
 }

fs/nfs/delegation.c

···
 
 static void nfs_do_free_delegation(struct nfs_delegation *delegation)
 {
-	if (delegation->cred)
-		put_rpccred(delegation->cred);
 	kfree(delegation);
 }
 
···
 
 static void nfs_free_delegation(struct nfs_delegation *delegation)
 {
+	if (delegation->cred) {
+		put_rpccred(delegation->cred);
+		delegation->cred = NULL;
+	}
 	call_rcu(&delegation->rcu, nfs_free_delegation_callback);
 }
 

fs/nfs/direct.c

···
 		pos += vec->iov_len;
 	}
 
+	/*
+	 * If no bytes were started, return the error, and let the
+	 * generic layer handle the completion.
+	 */
+	if (requested_bytes == 0) {
+		nfs_direct_req_release(dreq);
+		return result < 0 ? result : -EIO;
+	}
+
 	if (put_dreq(dreq))
 		nfs_direct_complete(dreq);
-
-	if (requested_bytes != 0)
-		return 0;
-
-	if (result < 0)
-		return result;
-	return -EIO;
+	return 0;
 }
 
 static ssize_t nfs_direct_read(struct kiocb *iocb, const struct iovec *iov,
···
 		pos += vec->iov_len;
 	}
 
+	/*
+	 * If no bytes were started, return the error, and let the
+	 * generic layer handle the completion.
+	 */
+	if (requested_bytes == 0) {
+		nfs_direct_req_release(dreq);
+		return result < 0 ? result : -EIO;
+	}
+
 	if (put_dreq(dreq))
 		nfs_direct_write_complete(dreq, dreq->inode);
-
-	if (requested_bytes != 0)
-		return 0;
-
-	if (result < 0)
-		return result;
-	return -EIO;
+	return 0;
 }
 
 static ssize_t nfs_direct_write(struct kiocb *iocb, const struct iovec *iov,

fs/nfs/inode.c

···
 	return ret;
 }
 
-static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
+static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
+	unsigned long ret = 0;
 
 	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
 			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
···
 		nfsi->change_attr = fattr->change_attr;
 		if (S_ISDIR(inode->i_mode))
 			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+		ret |= NFS_INO_INVALID_ATTR;
 	}
 	/* If we have atomic WCC data, we may update some attributes */
 	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
 			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
-			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime))
-			memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
+			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
+		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
+		ret |= NFS_INO_INVALID_ATTR;
+	}
 
 	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
 			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
 			&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
-			memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
-			if (S_ISDIR(inode->i_mode))
-				nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
+		if (S_ISDIR(inode->i_mode))
+			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+		ret |= NFS_INO_INVALID_ATTR;
 	}
 	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
 			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
 			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
-			&& nfsi->npages == 0)
-			i_size_write(inode, nfs_size_to_loff_t(fattr->size));
+			&& nfsi->npages == 0) {
+		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
+		ret |= NFS_INO_INVALID_ATTR;
+	}
+	return ret;
 }
 
 /**
···
 			| NFS_INO_REVAL_PAGECACHE);
 
 	/* Do atomic weak cache consistency updates */
-	nfs_wcc_update_inode(inode, fattr);
+	invalid |= nfs_wcc_update_inode(inode, fattr);
 
 	/* More cache consistency checks */
 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {

fs/nfs/internal.h

···
 extern struct nfs_client *nfs4_find_client_no_ident(const struct sockaddr *);
 extern struct nfs_client *nfs4_find_client_ident(int);
 extern struct nfs_client *
-nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *,
-			   int);
+nfs4_find_client_sessionid(const struct sockaddr *, struct nfs4_sessionid *);
 extern struct nfs_server *nfs_create_server(
 					const struct nfs_parsed_mount_data *,
 					struct nfs_fh *);

fs/nfs/nfs3acl.c

···
 	if (!nfs_server_capable(inode, NFS_CAP_ACLS))
 		goto out;
 
-	/* We are doing this here, because XDR marshalling can only
-	   return -ENOMEM. */
+	/* We are doing this here because XDR marshalling does not
+	 * return any results, it BUGs. */
 	status = -ENOSPC;
 	if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
 		goto out;

fs/nfs/nfs3xdr.c

···
 
 	encode_nfs_fh3(xdr, NFS_FH(args->inode));
 	encode_uint32(xdr, args->mask);
-	if (args->npages != 0)
-		xdr_write_pages(xdr, args->pages, 0, args->len);
 
 	base = req->rq_slen;
+	if (args->npages != 0)
+		xdr_write_pages(xdr, args->pages, 0, args->len);
+	else
+		xdr_reserve_space(xdr, NFS_ACL_INLINE_BUFSIZE);
+
 	error = nfsacl_encode(xdr->buf, base, args->inode,
 			    (args->mask & NFS_ACL) ?
 			    args->acl_access : NULL, 1, 0);

fs/nfs/nfs4filelayoutdev.c

···
 
 	/* ipv6 length plus port is legal */
 	if (rlen > INET6_ADDRSTRLEN + 8) {
-		dprintk("%s Invalid address, length %d\n", __func__,
+		dprintk("%s: Invalid address, length %d\n", __func__,
 			rlen);
 		goto out_err;
 	}
···
 	/* replace the port dots with dashes for the in4_pton() delimiter*/
 	for (i = 0; i < 2; i++) {
 		char *res = strrchr(buf, '.');
+		if (!res) {
+			dprintk("%s: Failed finding expected dots in port\n",
+				__func__);
+			goto out_free;
+		}
 		*res = '-';
 	}
 
···
 	port = htons((tmp[0] << 8) | (tmp[1]));
 
 	ds = nfs4_pnfs_ds_add(inode, ip_addr, port);
-	dprintk("%s Decoded address and port %s\n", __func__, buf);
+	dprintk("%s: Decoded address and port %s\n", __func__, buf);
 out_free:
 	kfree(buf);
 out_err:

fs/nfs/nfs4proc.c

···
 #include <linux/module.h>
 #include <linux/sunrpc/bc_xprt.h>
 #include <linux/xattr.h>
+#include <linux/utsname.h>
 
 #include "nfs4_fs.h"
 #include "delegation.h"
···
 	*p = htonl((u32)clp->cl_boot_time.tv_nsec);
 	args.verifier = &verifier;
 
-	while (1) {
-		args.id_len = scnprintf(args.id, sizeof(args.id),
-					"%s/%s %u",
-					clp->cl_ipaddr,
-					rpc_peeraddr2str(clp->cl_rpcclient,
-							 RPC_DISPLAY_ADDR),
-					clp->cl_id_uniquifier);
+	args.id_len = scnprintf(args.id, sizeof(args.id),
+				"%s/%s.%s/%u",
+				clp->cl_ipaddr,
+				init_utsname()->nodename,
+				init_utsname()->domainname,
+				clp->cl_rpcclient->cl_auth->au_flavor);
 
-		status = rpc_call_sync(clp->cl_rpcclient, &msg, 0);
-
-		if (status != -NFS4ERR_CLID_INUSE)
-			break;
-
-		if (signalled())
-			break;
-
-		if (++clp->cl_id_uniquifier == 0)
-			break;
-	}
-
-	status = nfs4_check_cl_exchange_flags(clp->cl_exchange_flags);
+	status = rpc_call_sync(clp->cl_rpcclient, &msg, 0);
+	if (!status)
+		status = nfs4_check_cl_exchange_flags(clp->cl_exchange_flags);
 	dprintk("<-- %s status= %d\n", __func__, status);
 	return status;
 }

fs/nfs/nfs4state.c

···
 	status = nfs4_proc_create_session(clp);
 	if (status != 0)
 		goto out;
-	status = nfs4_set_callback_sessionid(clp);
-	if (status != 0) {
-		printk(KERN_WARNING "Sessionid not set. No callback service\n");
-		nfs_callback_down(1);
-		status = 0;
-	}
 	nfs41_setup_state_renewal(clp);
 	nfs_mark_client_ready(clp, NFS_CS_READY);
 out:

fs/nfs/nfs4xdr.c

···
 	__be32 *p = xdr_inline_decode(xdr, 4);
 	if (unlikely(!p))
 		goto out_overflow;
-	if (!ntohl(*p++)) {
+	if (*p == xdr_zero) {
 		p = xdr_inline_decode(xdr, 4);
 		if (unlikely(!p))
 			goto out_overflow;
-		if (!ntohl(*p++))
+		if (*p == xdr_zero)
 			return -EAGAIN;
 		entry->eof = 1;
 		return -EBADCOOKIE;
···
 		goto out_overflow;
 	entry->prev_cookie = entry->cookie;
 	p = xdr_decode_hyper(p, &entry->cookie);
-	entry->len = ntohl(*p++);
+	entry->len = be32_to_cpup(p);
 
 	p = xdr_inline_decode(xdr, entry->len);
 	if (unlikely(!p))
···
 	entry->d_type = DT_UNKNOWN;
 	if (entry->fattr->valid & NFS_ATTR_FATTR_TYPE)
 		entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
-
-	if (verify_attr_len(xdr, p, len) < 0)
-		goto out_overflow;
 
 	return 0;
 

fs/nfs/pnfs.c

···
 {
 	struct pnfs_deviceid_cache *local = clp->cl_devid_cache;
 
-	dprintk("--> %s cl_devid_cache %p\n", __func__, clp->cl_devid_cache);
+	dprintk("--> %s ({%d})\n", __func__, atomic_read(&local->dc_ref));
 	if (atomic_dec_and_lock(&local->dc_ref, &clp->cl_lock)) {
 		int i;
 		/* Verify cache is empty */

fs/nfs/write.c

···
 	while (!list_empty(&list)) {
 		data = list_entry(list.next, struct nfs_write_data, pages);
 		list_del(&data->pages);
-		nfs_writedata_release(data);
+		nfs_writedata_free(data);
 	}
 	nfs_redirty_request(req);
 	return -ENOMEM;

fs/nfs_common/nfsacl.c

···
 	gid_t gid;
 };
 
+struct nfsacl_simple_acl {
+	struct posix_acl acl;
+	struct posix_acl_entry ace[4];
+};
+
 static int
 xdr_nfsace_encode(struct xdr_array2_desc *desc, void *elem)
 {
···
 	return 0;
 }
 
-unsigned int
-nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode,
-	      struct posix_acl *acl, int encode_entries, int typeflag)
+/**
+ * nfsacl_encode - Encode an NFSv3 ACL
+ *
+ * @buf: destination xdr_buf to contain XDR encoded ACL
+ * @base: byte offset in xdr_buf where XDR'd ACL begins
+ * @inode: inode of file whose ACL this is
+ * @acl: posix_acl to encode
+ * @encode_entries: whether to encode ACEs as well
+ * @typeflag: ACL type: NFS_ACL_DEFAULT or zero
+ *
+ * Returns size of encoded ACL in bytes or a negative errno value.
+ */
+int nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode,
+		  struct posix_acl *acl, int encode_entries, int typeflag)
 {
 	int entries = (acl && acl->a_count) ? max_t(int, acl->a_count, 4) : 0;
 	struct nfsacl_encode_desc nfsacl_desc = {
···
 		.uid = inode->i_uid,
 		.gid = inode->i_gid,
 	};
+	struct nfsacl_simple_acl aclbuf;
 	int err;
-	struct posix_acl *acl2 = NULL;
 
 	if (entries > NFS_ACL_MAX_ENTRIES ||
 	    xdr_encode_word(buf, base, entries))
 		return -EINVAL;
 	if (encode_entries && acl && acl->a_count == 3) {
-		/* Fake up an ACL_MASK entry. */
-		acl2 = posix_acl_alloc(4, GFP_KERNEL);
-		if (!acl2)
-			return -ENOMEM;
+		struct posix_acl *acl2 = &aclbuf.acl;
+
+		/* Avoid the use of posix_acl_alloc().  nfsacl_encode() is
+		 * invoked in contexts where a memory allocation failure is
+		 * fatal.  Fortunately this fake ACL is small enough to
+		 * construct on the stack. */
+		memset(acl2, 0, sizeof(acl2));
+		posix_acl_init(acl2, 4);
+
 		/* Insert entries in canonical order: other orders seem
 		 to confuse Solaris VxFS. */
 		acl2->a_entries[0] = acl->a_entries[0];  /* ACL_USER_OBJ */
···
 		nfsacl_desc.acl = acl2;
 	}
 	err = xdr_encode_array2(buf, base + 4, &nfsacl_desc.desc);
-	if (acl2)
-		posix_acl_release(acl2);
 	if (!err)
 		err = 8 + nfsacl_desc.desc.elem_size *
 			  nfsacl_desc.desc.array_len;
···
 	return 0;
 }
 
-unsigned int
-nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt,
-	      struct posix_acl **pacl)
+/**
+ * nfsacl_decode - Decode an NFSv3 ACL
+ *
+ * @buf: xdr_buf containing XDR'd ACL data to decode
+ * @base: byte offset in xdr_buf where XDR'd ACL begins
+ * @aclcnt: count of ACEs in decoded posix_acl
+ * @pacl: buffer in which to place decoded posix_acl
+ *
+ * Returns the length of the decoded ACL in bytes, or a negative errno value.
+ */
+int nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt,
+		  struct posix_acl **pacl)
 {
 	struct nfsacl_decode_desc nfsacl_desc = {
 		.desc = {

fs/posix_acl.c

···
 
 #include <linux/errno.h>
 
+EXPORT_SYMBOL(posix_acl_init);
 EXPORT_SYMBOL(posix_acl_alloc);
 EXPORT_SYMBOL(posix_acl_clone);
 EXPORT_SYMBOL(posix_acl_valid);
···
 EXPORT_SYMBOL(posix_acl_permission);
 
 /*
+ * Init a fresh posix_acl
+ */
+void
+posix_acl_init(struct posix_acl *acl, int count)
+{
+	atomic_set(&acl->a_refcount, 1);
+	acl->a_count = count;
+}
+
+/*
  * Allocate a new ACL with the specified number of entries.
  */
 struct posix_acl *
···
 	const size_t size = sizeof(struct posix_acl) +
 	                    count * sizeof(struct posix_acl_entry);
 	struct posix_acl *acl = kmalloc(size, flags);
-	if (acl) {
-		atomic_set(&acl->a_refcount, 1);
-		acl->a_count = count;
-	}
+	if (acl)
+		posix_acl_init(acl, count);
 	return acl;
 }
 

include/linux/nfsacl.h

···
 	return w;
 }
 
-extern unsigned int
+extern int
 nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode,
 	      struct posix_acl *acl, int encode_entries, int typeflag);
-extern unsigned int
+extern int
 nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt,
 	      struct posix_acl **pacl);
 

include/linux/posix_acl.h

···
 
 /* posix_acl.c */
 
+extern void posix_acl_init(struct posix_acl *, int);
 extern struct posix_acl *posix_acl_alloc(int, gfp_t);
 extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t);
 extern int posix_acl_valid(const struct posix_acl *);

include/linux/sunrpc/bc_xprt.h

···
 		return 1;
 	return 0;
 }
-static inline struct nfs4_sessionid *bc_xprt_sid(struct svc_rqst *rqstp)
-{
-	if (svc_is_backchannel(rqstp))
-		return (struct nfs4_sessionid *)
-			rqstp->rq_server->sv_bc_xprt->xpt_bc_sid;
-	return NULL;
-}
-
 #else /* CONFIG_NFS_V4_1 */
 static inline int xprt_setup_backchannel(struct rpc_xprt *xprt,
 					 unsigned int min_reqs)
···
 static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
 {
 	return 0;
-}
-
-static inline struct nfs4_sessionid *bc_xprt_sid(struct svc_rqst *rqstp)
-{
-	return NULL;
 }
 
 static inline void xprt_free_bc_request(struct rpc_rqst *req)

include/linux/sunrpc/svc_xprt.h

···
 	size_t			xpt_remotelen;	/* length of address */
 	struct rpc_wait_queue	xpt_bc_pending;	/* backchannel wait queue */
 	struct list_head	xpt_users;	/* callbacks on free */
-	void			*xpt_bc_sid;	/* back channel session ID */
 
 	struct net		*xpt_net;
 	struct rpc_xprt		*xpt_bc_xprt;	/* NFSv4.1 backchannel */

net/sunrpc/svcsock.c

···
  */
 static void svc_bc_sock_free(struct svc_xprt *xprt)
 {
-	if (xprt) {
-		kfree(xprt->xpt_bc_sid);
+	if (xprt)
 		kfree(container_of(xprt, struct svc_sock, sk_xprt));
-	}
 }
 #endif /* CONFIG_NFS_V4_1 */