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Diffstat (limited to 'fs/nfs/super.c')
-rw-r--r--fs/nfs/super.c147
1 files changed, 119 insertions, 28 deletions
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index b4148fc00f9f..2f8b1157daa2 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -141,7 +141,6 @@ static const match_table_t nfs_mount_option_tokens = {
{ Opt_resvport, "resvport" },
{ Opt_noresvport, "noresvport" },
{ Opt_fscache, "fsc" },
- { Opt_fscache_uniq, "fsc=%s" },
{ Opt_nofscache, "nofsc" },
{ Opt_port, "port=%s" },
@@ -171,6 +170,7 @@ static const match_table_t nfs_mount_option_tokens = {
{ Opt_mountaddr, "mountaddr=%s" },
{ Opt_lookupcache, "lookupcache=%s" },
+ { Opt_fscache_uniq, "fsc=%s" },
{ Opt_err, NULL }
};
@@ -423,15 +423,19 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
unsigned char blockbits;
unsigned long blockres;
struct nfs_fh *fh = NFS_FH(dentry->d_inode);
- struct nfs_fattr fattr;
- struct nfs_fsstat res = {
- .fattr = &fattr,
- };
- int error;
+ struct nfs_fsstat res;
+ int error = -ENOMEM;
+
+ res.fattr = nfs_alloc_fattr();
+ if (res.fattr == NULL)
+ goto out_err;
error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
+
+ nfs_free_fattr(res.fattr);
if (error < 0)
goto out_err;
+
buf->f_type = NFS_SUPER_MAGIC;
/*
@@ -1046,14 +1050,6 @@ static int nfs_parse_mount_options(char *raw,
kfree(mnt->fscache_uniq);
mnt->fscache_uniq = NULL;
break;
- case Opt_fscache_uniq:
- string = match_strdup(args);
- if (!string)
- goto out_nomem;
- kfree(mnt->fscache_uniq);
- mnt->fscache_uniq = string;
- mnt->options |= NFS_OPTION_FSCACHE;
- break;
/*
* options that take numeric values
@@ -1384,6 +1380,14 @@ static int nfs_parse_mount_options(char *raw,
return 0;
};
break;
+ case Opt_fscache_uniq:
+ string = match_strdup(args);
+ if (string == NULL)
+ goto out_nomem;
+ kfree(mnt->fscache_uniq);
+ mnt->fscache_uniq = string;
+ mnt->options |= NFS_OPTION_FSCACHE;
+ break;
/*
* Special options
@@ -2172,7 +2176,7 @@ static int nfs_get_sb(struct file_system_type *fs_type,
int error = -ENOMEM;
data = nfs_alloc_parsed_mount_data(3);
- mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+ mntfh = nfs_alloc_fhandle();
if (data == NULL || mntfh == NULL)
goto out_free_fh;
@@ -2247,7 +2251,7 @@ out:
kfree(data->fscache_uniq);
security_free_mnt_opts(&data->lsm_opts);
out_free_fh:
- kfree(mntfh);
+ nfs_free_fhandle(mntfh);
kfree(data);
return error;
@@ -2556,7 +2560,7 @@ static int nfs4_remote_get_sb(struct file_system_type *fs_type,
};
int error = -ENOMEM;
- mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+ mntfh = nfs_alloc_fhandle();
if (data == NULL || mntfh == NULL)
goto out_free_fh;
@@ -2614,7 +2618,7 @@ static int nfs4_remote_get_sb(struct file_system_type *fs_type,
out:
security_free_mnt_opts(&data->lsm_opts);
out_free_fh:
- kfree(mntfh);
+ nfs_free_fhandle(mntfh);
return error;
out_free:
@@ -2669,41 +2673,120 @@ out_freepage:
free_page((unsigned long)page);
}
+struct nfs_referral_count {
+ struct list_head list;
+ const struct task_struct *task;
+ unsigned int referral_count;
+};
+
+static LIST_HEAD(nfs_referral_count_list);
+static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
+
+static struct nfs_referral_count *nfs_find_referral_count(void)
+{
+ struct nfs_referral_count *p;
+
+ list_for_each_entry(p, &nfs_referral_count_list, list) {
+ if (p->task == current)
+ return p;
+ }
+ return NULL;
+}
+
+#define NFS_MAX_NESTED_REFERRALS 2
+
+static int nfs_referral_loop_protect(void)
+{
+ struct nfs_referral_count *p, *new;
+ int ret = -ENOMEM;
+
+ new = kmalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ goto out;
+ new->task = current;
+ new->referral_count = 1;
+
+ ret = 0;
+ spin_lock(&nfs_referral_count_list_lock);
+ p = nfs_find_referral_count();
+ if (p != NULL) {
+ if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
+ ret = -ELOOP;
+ else
+ p->referral_count++;
+ } else {
+ list_add(&new->list, &nfs_referral_count_list);
+ new = NULL;
+ }
+ spin_unlock(&nfs_referral_count_list_lock);
+ kfree(new);
+out:
+ return ret;
+}
+
+static void nfs_referral_loop_unprotect(void)
+{
+ struct nfs_referral_count *p;
+
+ spin_lock(&nfs_referral_count_list_lock);
+ p = nfs_find_referral_count();
+ p->referral_count--;
+ if (p->referral_count == 0)
+ list_del(&p->list);
+ else
+ p = NULL;
+ spin_unlock(&nfs_referral_count_list_lock);
+ kfree(p);
+}
+
static int nfs_follow_remote_path(struct vfsmount *root_mnt,
const char *export_path, struct vfsmount *mnt_target)
{
+ struct nameidata *nd = NULL;
struct mnt_namespace *ns_private;
- struct nameidata nd;
struct super_block *s;
int ret;
+ nd = kmalloc(sizeof(*nd), GFP_KERNEL);
+ if (nd == NULL)
+ return -ENOMEM;
+
ns_private = create_mnt_ns(root_mnt);
ret = PTR_ERR(ns_private);
if (IS_ERR(ns_private))
goto out_mntput;
+ ret = nfs_referral_loop_protect();
+ if (ret != 0)
+ goto out_put_mnt_ns;
+
ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
- export_path, LOOKUP_FOLLOW, &nd);
+ export_path, LOOKUP_FOLLOW, nd);
+ nfs_referral_loop_unprotect();
put_mnt_ns(ns_private);
if (ret != 0)
goto out_err;
- s = nd.path.mnt->mnt_sb;
+ s = nd->path.mnt->mnt_sb;
atomic_inc(&s->s_active);
mnt_target->mnt_sb = s;
- mnt_target->mnt_root = dget(nd.path.dentry);
+ mnt_target->mnt_root = dget(nd->path.dentry);
/* Correct the device pathname */
- nfs_fix_devname(&nd.path, mnt_target);
+ nfs_fix_devname(&nd->path, mnt_target);
- path_put(&nd.path);
+ path_put(&nd->path);
+ kfree(nd);
down_write(&s->s_umount);
return 0;
+out_put_mnt_ns:
+ put_mnt_ns(ns_private);
out_mntput:
mntput(root_mnt);
out_err:
+ kfree(nd);
return ret;
}
@@ -2874,17 +2957,21 @@ static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
struct super_block *s;
struct nfs_server *server;
struct dentry *mntroot;
- struct nfs_fh mntfh;
+ struct nfs_fh *mntfh;
int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
struct nfs_sb_mountdata sb_mntdata = {
.mntflags = flags,
};
- int error;
+ int error = -ENOMEM;
dprintk("--> nfs4_referral_get_sb()\n");
+ mntfh = nfs_alloc_fhandle();
+ if (mntfh == NULL)
+ goto out_err_nofh;
+
/* create a new volume representation */
- server = nfs4_create_referral_server(data, &mntfh);
+ server = nfs4_create_referral_server(data, mntfh);
if (IS_ERR(server)) {
error = PTR_ERR(server);
goto out_err_noserver;
@@ -2916,7 +3003,7 @@ static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
nfs_fscache_get_super_cookie(s, NULL, data);
}
- mntroot = nfs4_get_root(s, &mntfh);
+ mntroot = nfs4_get_root(s, mntfh);
if (IS_ERR(mntroot)) {
error = PTR_ERR(mntroot);
goto error_splat_super;
@@ -2933,12 +3020,15 @@ static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
security_sb_clone_mnt_opts(data->sb, s);
+ nfs_free_fhandle(mntfh);
dprintk("<-- nfs4_referral_get_sb() = 0\n");
return 0;
out_err_nosb:
nfs_free_server(server);
out_err_noserver:
+ nfs_free_fhandle(mntfh);
+out_err_nofh:
dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
return error;
@@ -2947,6 +3037,7 @@ error_splat_super:
bdi_unregister(&server->backing_dev_info);
error_splat_bdi:
deactivate_locked_super(s);
+ nfs_free_fhandle(mntfh);
dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
return error;
}
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