Commit 33852a1f authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Reduce the NFS mount code stack usage. 

This appears to fix the Oops reported in
  http://bugzilla.kernel.org/show_bug.cgi?id=10826



Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 945754a1

fs/nfs/super.c

+40 −28
Original line number Diff line number Diff line
@@ -1216,8 +1216,6 @@ static int nfs_validate_mount_data(void *options, 
{

	struct nfs_mount_data *data = (struct nfs_mount_data *)options;



	memset(args, 0, sizeof(*args));



	if (data == NULL)

		goto out_no_data;
@@ -1585,24 +1583,29 @@ static int nfs_get_sb(struct file_system_type *fs_type, 
{

	struct nfs_server *server = NULL;

	struct super_block *s;

	struct nfs_fh mntfh;

	struct nfs_parsed_mount_data data;

	struct nfs_parsed_mount_data *data;

	struct nfs_fh *mntfh;

	struct dentry *mntroot;

	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;

	struct nfs_sb_mountdata sb_mntdata = {

		.mntflags = flags,

	};

	int error;

	int error = -ENOMEM;



	security_init_mnt_opts(&data.lsm_opts);

	data = kzalloc(sizeof(*data), GFP_KERNEL);

	mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);

	if (data == NULL || mntfh == NULL)

		goto out_free_fh;



	security_init_mnt_opts(&data->lsm_opts);



	/* Validate the mount data */

	error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);

	error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);

	if (error < 0)

		goto out;



	/* Get a volume representation */

	server = nfs_create_server(&data, &mntfh);

	server = nfs_create_server(data, mntfh);

	if (IS_ERR(server)) {

		error = PTR_ERR(server);

		goto out;
@@ -1630,16 +1633,16 @@ static int nfs_get_sb(struct file_system_type *fs_type, 


	if (!s->s_root) {

		/* initial superblock/root creation */

		nfs_fill_super(s, &data);

		nfs_fill_super(s, data);

	}



	mntroot = nfs_get_root(s, &mntfh);

	mntroot = nfs_get_root(s, mntfh);

	if (IS_ERR(mntroot)) {

		error = PTR_ERR(mntroot);

		goto error_splat_super;

	}



	error = security_sb_set_mnt_opts(s, &data.lsm_opts);

	error = security_sb_set_mnt_opts(s, &data->lsm_opts);

	if (error)

		goto error_splat_root;
@@ -1649,9 +1652,12 @@ static int nfs_get_sb(struct file_system_type *fs_type, 
	error = 0;



out:

	kfree(data.nfs_server.hostname);

	kfree(data.mount_server.hostname);

	security_free_mnt_opts(&data.lsm_opts);

	kfree(data->nfs_server.hostname);

	kfree(data->mount_server.hostname);

	security_free_mnt_opts(&data->lsm_opts);

out_free_fh:

	kfree(mntfh);

	kfree(data);

	return error;



out_err_nosb:
@@ -1800,8 +1806,6 @@ static int nfs4_validate_mount_data(void *options, 
	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;

	char *c;



	memset(args, 0, sizeof(*args));



	if (data == NULL)

		goto out_no_data;
@@ -1959,26 +1963,31 @@ static int nfs4_validate_mount_data(void *options, 
static int nfs4_get_sb(struct file_system_type *fs_type,

	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)

{

	struct nfs_parsed_mount_data data;

	struct nfs_parsed_mount_data *data;

	struct super_block *s;

	struct nfs_server *server;

	struct nfs_fh mntfh;

	struct nfs_fh *mntfh;

	struct dentry *mntroot;

	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;

	struct nfs_sb_mountdata sb_mntdata = {

		.mntflags = flags,

	};

	int error;

	int error = -ENOMEM;



	security_init_mnt_opts(&data.lsm_opts);

	data = kzalloc(sizeof(*data), GFP_KERNEL);

	mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);

	if (data == NULL || mntfh == NULL)

		goto out_free_fh;



	security_init_mnt_opts(&data->lsm_opts);



	/* Validate the mount data */

	error = nfs4_validate_mount_data(raw_data, &data, dev_name);

	error = nfs4_validate_mount_data(raw_data, data, dev_name);

	if (error < 0)

		goto out;



	/* Get a volume representation */

	server = nfs4_create_server(&data, &mntfh);

	server = nfs4_create_server(data, mntfh);

	if (IS_ERR(server)) {

		error = PTR_ERR(server);

		goto out;
@@ -2009,13 +2018,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type, 
		nfs4_fill_super(s);

	}



	mntroot = nfs4_get_root(s, &mntfh);

	mntroot = nfs4_get_root(s, mntfh);

	if (IS_ERR(mntroot)) {

		error = PTR_ERR(mntroot);

		goto error_splat_super;

	}



	error = security_sb_set_mnt_opts(s, &data.lsm_opts);

	error = security_sb_set_mnt_opts(s, &data->lsm_opts);

	if (error)

		goto error_splat_root;
@@ -2025,10 +2034,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type, 
	error = 0;



out:

	kfree(data.client_address);

	kfree(data.nfs_server.export_path);

	kfree(data.nfs_server.hostname);

	security_free_mnt_opts(&data.lsm_opts);

	kfree(data->client_address);

	kfree(data->nfs_server.export_path);

	kfree(data->nfs_server.hostname);

	security_free_mnt_opts(&data->lsm_opts);

out_free_fh:

	kfree(mntfh);

	kfree(data);

	return error;



out_free: