1 files changed, 141 insertions, 88 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index a03b9c6f948..084af1060d7 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -497,7 +497,8 @@ static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 	static const struct {
 		rpc_authflavor_t flavour;
 		const char *str;
-	} sec_flavours[] = {
+	} sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
+		/* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 		{ RPC_AUTH_NULL, "null" },
 		{ RPC_AUTH_UNIX, "sys" },
 		{ RPC_AUTH_GSS_KRB5, "krb5" },
@@ -923,8 +924,7 @@ static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 		data->mount_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-		data->auth_flavors[0]	= RPC_AUTH_MAXFLAVOR;
-		data->auth_flavor_len	= 0;
+		data->selected_flavor	= RPC_AUTH_MAXFLAVOR;
 		data->minorversion	= 0;
 		data->need_mount	= true;
 		data->net		= current->nsproxy->net_ns;
@@ -1019,14 +1019,53 @@ static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 	}
 }
 
-static void nfs_set_auth_parsed_mount_data(struct nfs_parsed_mount_data *data,
-		rpc_authflavor_t pseudoflavor)
+/*
+ * Add 'flavor' to 'auth_info' if not already present.
+ * Returns true if 'flavor' ends up in the list, false otherwise
+ */
+static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
+			      rpc_authflavor_t flavor)
 {
-	data->auth_flavors[0] = pseudoflavor;
-	data->auth_flavor_len = 1;
+	unsigned int i;
+	unsigned int max_flavor_len = (sizeof(auth_info->flavors) /
+				       sizeof(auth_info->flavors[0]));
+
+	/* make sure this flavor isn't already in the list */
+	for (i = 0; i < auth_info->flavor_len; i++) {
+		if (flavor == auth_info->flavors[i])
+			return true;
+	}
+
+	if (auth_info->flavor_len + 1 >= max_flavor_len) {
+		dfprintk(MOUNT, "NFS: too many sec= flavors\n");
+		return false;
+	}
+
+	auth_info->flavors[auth_info->flavor_len++] = flavor;
+	return true;
 }
 
 /*
+ * Return true if 'match' is in auth_info or auth_info is empty.
+ * Return false otherwise.
+ */
+bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
+			 rpc_authflavor_t match)
+{
+	int i;
+
+	if (!auth_info->flavor_len)
+		return true;
+
+	for (i = 0; i < auth_info->flavor_len; i++) {
+		if (auth_info->flavors[i] == match)
+			return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL_GPL(nfs_auth_info_match);
+
+/*
  * Parse the value of the 'sec=' option.
  */
 static int nfs_parse_security_flavors(char *value,
@@ -1034,49 +1073,55 @@ static int nfs_parse_security_flavors(char *value,
 {
 	substring_t args[MAX_OPT_ARGS];
 	rpc_authflavor_t pseudoflavor;
+	char *p;
 
 	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 
-	switch (match_token(value, nfs_secflavor_tokens, args)) {
-	case Opt_sec_none:
-		pseudoflavor = RPC_AUTH_NULL;
-		break;
-	case Opt_sec_sys:
-		pseudoflavor = RPC_AUTH_UNIX;
-		break;
-	case Opt_sec_krb5:
-		pseudoflavor = RPC_AUTH_GSS_KRB5;
-		break;
-	case Opt_sec_krb5i:
-		pseudoflavor = RPC_AUTH_GSS_KRB5I;
-		break;
-	case Opt_sec_krb5p:
-		pseudoflavor = RPC_AUTH_GSS_KRB5P;
-		break;
-	case Opt_sec_lkey:
-		pseudoflavor = RPC_AUTH_GSS_LKEY;
-		break;
-	case Opt_sec_lkeyi:
-		pseudoflavor = RPC_AUTH_GSS_LKEYI;
-		break;
-	case Opt_sec_lkeyp:
-		pseudoflavor = RPC_AUTH_GSS_LKEYP;
-		break;
-	case Opt_sec_spkm:
-		pseudoflavor = RPC_AUTH_GSS_SPKM;
-		break;
-	case Opt_sec_spkmi:
-		pseudoflavor = RPC_AUTH_GSS_SPKMI;
-		break;
-	case Opt_sec_spkmp:
-		pseudoflavor = RPC_AUTH_GSS_SPKMP;
-		break;
-	default:
-		return 0;
+	while ((p = strsep(&value, ":")) != NULL) {
+		switch (match_token(p, nfs_secflavor_tokens, args)) {
+		case Opt_sec_none:
+			pseudoflavor = RPC_AUTH_NULL;
+			break;
+		case Opt_sec_sys:
+			pseudoflavor = RPC_AUTH_UNIX;
+			break;
+		case Opt_sec_krb5:
+			pseudoflavor = RPC_AUTH_GSS_KRB5;
+			break;
+		case Opt_sec_krb5i:
+			pseudoflavor = RPC_AUTH_GSS_KRB5I;
+			break;
+		case Opt_sec_krb5p:
+			pseudoflavor = RPC_AUTH_GSS_KRB5P;
+			break;
+		case Opt_sec_lkey:
+			pseudoflavor = RPC_AUTH_GSS_LKEY;
+			break;
+		case Opt_sec_lkeyi:
+			pseudoflavor = RPC_AUTH_GSS_LKEYI;
+			break;
+		case Opt_sec_lkeyp:
+			pseudoflavor = RPC_AUTH_GSS_LKEYP;
+			break;
+		case Opt_sec_spkm:
+			pseudoflavor = RPC_AUTH_GSS_SPKM;
+			break;
+		case Opt_sec_spkmi:
+			pseudoflavor = RPC_AUTH_GSS_SPKMI;
+			break;
+		case Opt_sec_spkmp:
+			pseudoflavor = RPC_AUTH_GSS_SPKMP;
+			break;
+		default:
+			dfprintk(MOUNT,
+				 "NFS: sec= option '%s' not recognized\n", p);
+			return 0;
+		}
+
+		if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
+			return 0;
 	}
 
-	mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-	nfs_set_auth_parsed_mount_data(mnt, pseudoflavor);
 	return 1;
 }
 
@@ -1569,7 +1614,7 @@ static int nfs_parse_mount_options(char *raw,
 		goto out_minorversion_mismatch;
 
 	if (mnt->options & NFS_OPTION_MIGRATION &&
-	    mnt->version != 4 && mnt->minorversion != 0)
+	    (mnt->version != 4 || mnt->minorversion != 0))
 		goto out_migration_misuse;
 
 	/*
@@ -1623,12 +1668,14 @@ out_security_failure:
 }
 
 /*
- * Ensure that the specified authtype in args->auth_flavors[0] is supported by
- * the server. Returns 0 if it's ok, and -EACCES if not.
+ * Ensure that a specified authtype in args->auth_info is supported by
+ * the server. Returns 0 and sets args->selected_flavor if it's ok, and
+ * -EACCES if not.
  */
-static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
+static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
 			rpc_authflavor_t *server_authlist, unsigned int count)
 {
+	rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
 	unsigned int i;
 
 	/*
@@ -1640,17 +1687,20 @@ static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
 	 * can be used.
 	 */
 	for (i = 0; i < count; i++) {
-		if (args->auth_flavors[0] == server_authlist[i] ||
-		    server_authlist[i] == RPC_AUTH_NULL)
+		flavor = server_authlist[i];
+
+		if (nfs_auth_info_match(&args->auth_info, flavor) ||
+		    flavor == RPC_AUTH_NULL)
 			goto out;
 	}
 
-	dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
-		args->auth_flavors[0]);
+	dfprintk(MOUNT,
+		 "NFS: specified auth flavors not supported by server\n");
 	return -EACCES;
 
 out:
-	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
+	args->selected_flavor = flavor;
+	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
 	return 0;
 }
 
@@ -1738,9 +1788,10 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 	 * Was a sec= authflavor specified in the options? First, verify
 	 * whether the server supports it, and then just try to use it if so.
 	 */
-	if (args->auth_flavor_len > 0) {
-		status = nfs_verify_authflavor(args, authlist, authlist_len);
-		dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
+	if (args->auth_info.flavor_len > 0) {
+		status = nfs_verify_authflavors(args, authlist, authlist_len);
+		dfprintk(MOUNT, "NFS: using auth flavor %u\n",
+			 args->selected_flavor);
 		if (status)
 			return ERR_PTR(status);
 		return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
@@ -1769,7 +1820,7 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 			/* Fallthrough */
 		}
 		dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
-		nfs_set_auth_parsed_mount_data(args, flavor);
+		args->selected_flavor = flavor;
 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
 		if (!IS_ERR(server))
 			return server;
@@ -1785,7 +1836,7 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 
 	/* Last chance! Try AUTH_UNIX */
 	dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
-	nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+	args->selected_flavor = RPC_AUTH_UNIX;
 	return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
 }
 
@@ -1972,9 +2023,9 @@ static int nfs23_validate_mount_data(void *options,
 		args->bsize		= data->bsize;
 
 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
-			nfs_set_auth_parsed_mount_data(args, data->pseudoflavor);
+			args->selected_flavor = data->pseudoflavor;
 		else
-			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+			args->selected_flavor = RPC_AUTH_UNIX;
 		if (!args->nfs_server.hostname)
 			goto out_nomem;
 
@@ -2108,9 +2159,6 @@ static int nfs_validate_text_mount_data(void *options,
 
 	nfs_set_port(sap, &args->nfs_server.port, port);
 
-	if (args->auth_flavor_len > 1)
-		goto out_bad_auth;
-
 	return nfs_parse_devname(dev_name,
 				   &args->nfs_server.hostname,
 				   max_namelen,
@@ -2130,21 +2178,31 @@ out_invalid_transport_udp:
 out_no_address:
 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
 	return -EINVAL;
-
-out_bad_auth:
-	dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
-	return -EINVAL;
 }
 
+#define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
+		| NFS_MOUNT_SECURE \
+		| NFS_MOUNT_TCP \
+		| NFS_MOUNT_VER3 \
+		| NFS_MOUNT_KERBEROS \
+		| NFS_MOUNT_NONLM \
+		| NFS_MOUNT_BROKEN_SUID \
+		| NFS_MOUNT_STRICTLOCK \
+		| NFS_MOUNT_UNSHARED \
+		| NFS_MOUNT_NORESVPORT \
+		| NFS_MOUNT_LEGACY_INTERFACE)
+
 static int
 nfs_compare_remount_data(struct nfs_server *nfss,
 			 struct nfs_parsed_mount_data *data)
 {
-	if (data->flags != nfss->flags ||
+	if ((data->flags ^ nfss->flags) & NFS_MOUNT_CMP_FLAGMASK ||
 	    data->rsize != nfss->rsize ||
 	    data->wsize != nfss->wsize ||
+	    data->version != nfss->nfs_client->rpc_ops->version ||
+	    data->minorversion != nfss->nfs_client->cl_minorversion ||
 	    data->retrans != nfss->client->cl_timeout->to_retries ||
-	    data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
+	    data->selected_flavor != nfss->client->cl_auth->au_flavor ||
 	    data->acregmin != nfss->acregmin / HZ ||
 	    data->acregmax != nfss->acregmax / HZ ||
 	    data->acdirmin != nfss->acdirmin / HZ ||
@@ -2169,6 +2227,8 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 	struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
 	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
 
+	sync_filesystem(sb);
+
 	/*
 	 * Userspace mount programs that send binary options generally send
 	 * them populated with default values. We have no way to know which
@@ -2189,7 +2249,8 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 	data->rsize = nfss->rsize;
 	data->wsize = nfss->wsize;
 	data->retrans = nfss->client->cl_timeout->to_retries;
-	nfs_set_auth_parsed_mount_data(data, nfss->client->cl_auth->au_flavor);
+	data->selected_flavor = nfss->client->cl_auth->au_flavor;
+	data->auth_info = nfss->auth_info;
 	data->acregmin = nfss->acregmin / HZ;
 	data->acregmax = nfss->acregmax / HZ;
 	data->acdirmin = nfss->acdirmin / HZ;
@@ -2197,12 +2258,15 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
 	data->nfs_server.port = nfss->port;
 	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
+	data->version = nfsvers;
+	data->minorversion = nfss->nfs_client->cl_minorversion;
+	data->net = current->nsproxy->net_ns;
 	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
 		data->nfs_server.addrlen);
 
 	/* overwrite those values with any that were specified */
-	error = nfs_parse_mount_options((char *)options, data);
-	if (error < 0)
+	error = -EINVAL;
+	if (!nfs_parse_mount_options((char *)options, data))
 		goto out;
 
 	/*
@@ -2296,18 +2360,6 @@ void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
  	nfs_initialise_sb(sb);
 }
 
-#define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
-		| NFS_MOUNT_SECURE \
-		| NFS_MOUNT_TCP \
-		| NFS_MOUNT_VER3 \
-		| NFS_MOUNT_KERBEROS \
-		| NFS_MOUNT_NONLM \
-		| NFS_MOUNT_BROKEN_SUID \
-		| NFS_MOUNT_STRICTLOCK \
-		| NFS_MOUNT_UNSHARED \
-		| NFS_MOUNT_NORESVPORT \
-		| NFS_MOUNT_LEGACY_INTERFACE)
-
 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
 {
 	const struct nfs_server *a = s->s_fs_info;
@@ -2332,7 +2384,7 @@ static int nfs_compare_mount_options(const struct super_block *s, const struct n
 		goto Ebusy;
 	if (a->acdirmax != b->acdirmax)
 		goto Ebusy;
-	if (b->flags & NFS_MOUNT_SECFLAVOUR &&
+	if (b->auth_info.flavor_len > 0 &&
 	   clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
 		goto Ebusy;
 	return 1;
@@ -2530,6 +2582,7 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server,
 			mntroot = ERR_PTR(error);
 			goto error_splat_bdi;
 		}
+		server->super = s;
 	}
 
 	if (!s->s_root) {
@@ -2713,9 +2766,9 @@ static int nfs4_validate_mount_data(void *options,
 					   data->auth_flavours,
 					   sizeof(pseudoflavor)))
 				return -EFAULT;
-			nfs_set_auth_parsed_mount_data(args, pseudoflavor);
+			args->selected_flavor = pseudoflavor;
 		} else
-			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+			args->selected_flavor = RPC_AUTH_UNIX;
 
 		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
 		if (IS_ERR(c))