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: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 2a4a024..dac663d 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1216,8 +1216,6 @@
{
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 @@
{
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 @@
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 @@
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 @@
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_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 @@
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 @@
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: