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path: root/fs/namespace.c
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Diffstat (limited to 'fs/namespace.c')
-rw-r--r--fs/namespace.c106
1 files changed, 50 insertions, 56 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index f30b11e2240e..411728c0c8bb 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -112,9 +112,13 @@ struct vfsmount *alloc_vfsmnt(const char *name)
int err;
err = mnt_alloc_id(mnt);
- if (err) {
- kmem_cache_free(mnt_cache, mnt);
- return NULL;
+ if (err)
+ goto out_free_cache;
+
+ if (name) {
+ mnt->mnt_devname = kstrdup(name, GFP_KERNEL);
+ if (!mnt->mnt_devname)
+ goto out_free_id;
}
atomic_set(&mnt->mnt_count, 1);
@@ -127,16 +131,14 @@ struct vfsmount *alloc_vfsmnt(const char *name)
INIT_LIST_HEAD(&mnt->mnt_slave_list);
INIT_LIST_HEAD(&mnt->mnt_slave);
atomic_set(&mnt->__mnt_writers, 0);
- if (name) {
- int size = strlen(name) + 1;
- char *newname = kmalloc(size, GFP_KERNEL);
- if (newname) {
- memcpy(newname, name, size);
- mnt->mnt_devname = newname;
- }
- }
}
return mnt;
+
+out_free_id:
+ mnt_free_id(mnt);
+out_free_cache:
+ kmem_cache_free(mnt_cache, mnt);
+ return NULL;
}
/*
@@ -1128,27 +1130,27 @@ static int do_umount(struct vfsmount *mnt, int flags)
asmlinkage long sys_umount(char __user * name, int flags)
{
- struct nameidata nd;
+ struct path path;
int retval;
- retval = __user_walk(name, LOOKUP_FOLLOW, &nd);
+ retval = user_path(name, &path);
if (retval)
goto out;
retval = -EINVAL;
- if (nd.path.dentry != nd.path.mnt->mnt_root)
+ if (path.dentry != path.mnt->mnt_root)
goto dput_and_out;
- if (!check_mnt(nd.path.mnt))
+ if (!check_mnt(path.mnt))
goto dput_and_out;
retval = -EPERM;
if (!capable(CAP_SYS_ADMIN))
goto dput_and_out;
- retval = do_umount(nd.path.mnt, flags);
+ retval = do_umount(path.mnt, flags);
dput_and_out:
/* we mustn't call path_put() as that would clear mnt_expiry_mark */
- dput(nd.path.dentry);
- mntput_no_expire(nd.path.mnt);
+ dput(path.dentry);
+ mntput_no_expire(path.mnt);
out:
return retval;
}
@@ -1972,7 +1974,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
struct fs_struct *fs)
{
struct mnt_namespace *new_ns;
- struct vfsmount *rootmnt = NULL, *pwdmnt = NULL, *altrootmnt = NULL;
+ struct vfsmount *rootmnt = NULL, *pwdmnt = NULL;
struct vfsmount *p, *q;
new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
@@ -2015,10 +2017,6 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
pwdmnt = p;
fs->pwd.mnt = mntget(q);
}
- if (p == fs->altroot.mnt) {
- altrootmnt = p;
- fs->altroot.mnt = mntget(q);
- }
}
p = next_mnt(p, mnt_ns->root);
q = next_mnt(q, new_ns->root);
@@ -2029,8 +2027,6 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
mntput(rootmnt);
if (pwdmnt)
mntput(pwdmnt);
- if (altrootmnt)
- mntput(altrootmnt);
return new_ns;
}
@@ -2183,28 +2179,26 @@ asmlinkage long sys_pivot_root(const char __user * new_root,
const char __user * put_old)
{
struct vfsmount *tmp;
- struct nameidata new_nd, old_nd;
- struct path parent_path, root_parent, root;
+ struct path new, old, parent_path, root_parent, root;
int error;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- error = __user_walk(new_root, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
- &new_nd);
+ error = user_path_dir(new_root, &new);
if (error)
goto out0;
error = -EINVAL;
- if (!check_mnt(new_nd.path.mnt))
+ if (!check_mnt(new.mnt))
goto out1;
- error = __user_walk(put_old, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &old_nd);
+ error = user_path_dir(put_old, &old);
if (error)
goto out1;
- error = security_sb_pivotroot(&old_nd.path, &new_nd.path);
+ error = security_sb_pivotroot(&old, &new);
if (error) {
- path_put(&old_nd.path);
+ path_put(&old);
goto out1;
}
@@ -2213,69 +2207,69 @@ asmlinkage long sys_pivot_root(const char __user * new_root,
path_get(&current->fs->root);
read_unlock(&current->fs->lock);
down_write(&namespace_sem);
- mutex_lock(&old_nd.path.dentry->d_inode->i_mutex);
+ mutex_lock(&old.dentry->d_inode->i_mutex);
error = -EINVAL;
- if (IS_MNT_SHARED(old_nd.path.mnt) ||
- IS_MNT_SHARED(new_nd.path.mnt->mnt_parent) ||
+ if (IS_MNT_SHARED(old.mnt) ||
+ IS_MNT_SHARED(new.mnt->mnt_parent) ||
IS_MNT_SHARED(root.mnt->mnt_parent))
goto out2;
if (!check_mnt(root.mnt))
goto out2;
error = -ENOENT;
- if (IS_DEADDIR(new_nd.path.dentry->d_inode))
+ if (IS_DEADDIR(new.dentry->d_inode))
goto out2;
- if (d_unhashed(new_nd.path.dentry) && !IS_ROOT(new_nd.path.dentry))
+ if (d_unhashed(new.dentry) && !IS_ROOT(new.dentry))
goto out2;
- if (d_unhashed(old_nd.path.dentry) && !IS_ROOT(old_nd.path.dentry))
+ if (d_unhashed(old.dentry) && !IS_ROOT(old.dentry))
goto out2;
error = -EBUSY;
- if (new_nd.path.mnt == root.mnt ||
- old_nd.path.mnt == root.mnt)
+ if (new.mnt == root.mnt ||
+ old.mnt == root.mnt)
goto out2; /* loop, on the same file system */
error = -EINVAL;
if (root.mnt->mnt_root != root.dentry)
goto out2; /* not a mountpoint */
if (root.mnt->mnt_parent == root.mnt)
goto out2; /* not attached */
- if (new_nd.path.mnt->mnt_root != new_nd.path.dentry)
+ if (new.mnt->mnt_root != new.dentry)
goto out2; /* not a mountpoint */
- if (new_nd.path.mnt->mnt_parent == new_nd.path.mnt)
+ if (new.mnt->mnt_parent == new.mnt)
goto out2; /* not attached */
/* make sure we can reach put_old from new_root */
- tmp = old_nd.path.mnt;
+ tmp = old.mnt;
spin_lock(&vfsmount_lock);
- if (tmp != new_nd.path.mnt) {
+ if (tmp != new.mnt) {
for (;;) {
if (tmp->mnt_parent == tmp)
goto out3; /* already mounted on put_old */
- if (tmp->mnt_parent == new_nd.path.mnt)
+ if (tmp->mnt_parent == new.mnt)
break;
tmp = tmp->mnt_parent;
}
- if (!is_subdir(tmp->mnt_mountpoint, new_nd.path.dentry))
+ if (!is_subdir(tmp->mnt_mountpoint, new.dentry))
goto out3;
- } else if (!is_subdir(old_nd.path.dentry, new_nd.path.dentry))
+ } else if (!is_subdir(old.dentry, new.dentry))
goto out3;
- detach_mnt(new_nd.path.mnt, &parent_path);
+ detach_mnt(new.mnt, &parent_path);
detach_mnt(root.mnt, &root_parent);
/* mount old root on put_old */
- attach_mnt(root.mnt, &old_nd.path);
+ attach_mnt(root.mnt, &old);
/* mount new_root on / */
- attach_mnt(new_nd.path.mnt, &root_parent);
+ attach_mnt(new.mnt, &root_parent);
touch_mnt_namespace(current->nsproxy->mnt_ns);
spin_unlock(&vfsmount_lock);
- chroot_fs_refs(&root, &new_nd.path);
- security_sb_post_pivotroot(&root, &new_nd.path);
+ chroot_fs_refs(&root, &new);
+ security_sb_post_pivotroot(&root, &new);
error = 0;
path_put(&root_parent);
path_put(&parent_path);
out2:
- mutex_unlock(&old_nd.path.dentry->d_inode->i_mutex);
+ mutex_unlock(&old.dentry->d_inode->i_mutex);
up_write(&namespace_sem);
path_put(&root);
- path_put(&old_nd.path);
+ path_put(&old);
out1:
- path_put(&new_nd.path);
+ path_put(&new);
out0:
return error;
out3:
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-16 04:28:20 +0000