Create a helper finish_open_simple() that opens the file with the original
dentry. Handle the error case here as well to simplify callers.
Call this helper right after ->tmpfile() is called.
Next patch will change the tmpfile API and move this call into tmpfile
instances.
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
---
fs/namei.c | 79 ++++++++++++++++++----------------------------
include/linux/fs.h | 9 ++++++
2 files changed, 40 insertions(+), 48 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 652d09ae66fb..4faf7e743664 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3583,44 +3583,43 @@ static int do_open(struct nameidata *nd,
* On non-idmapped mounts or if permission checking is to be performed on the
* raw inode simply passs init_user_ns.
*/
-static struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns,
- struct dentry *dentry, umode_t mode, int open_flag)
+static int vfs_tmpfile(struct user_namespace *mnt_userns,
+ const struct path *parentpath,
+ struct file *file, umode_t mode)
{
- struct dentry *child = NULL;
- struct inode *dir = dentry->d_inode;
+ struct dentry *child;
+ struct inode *dir = d_inode(parentpath->dentry);
struct inode *inode;
int error;
/* we want directory to be writable */
error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
if (error)
- goto out_err;
- error = -EOPNOTSUPP;
+ return error;
if (!dir->i_op->tmpfile)
- goto out_err;
- error = -ENOMEM;
- child = d_alloc(dentry, &slash_name);
+ return -EOPNOTSUPP;
+ child = d_alloc(parentpath->dentry, &slash_name);
if (unlikely(!child))
- goto out_err;
+ return -ENOMEM;
+ file->f_path.mnt = parentpath->mnt;
+ file->f_path.dentry = child;
mode = vfs_prepare_mode(mnt_userns, dir, mode, mode, mode);
error = dir->i_op->tmpfile(mnt_userns, dir, child, mode);
+ error = finish_open_simple(file, error);
+ dput(child);
if (error)
- goto out_err;
- error = -ENOENT;
+ return error;
+ error = may_open(mnt_userns, &file->f_path, 0, file->f_flags);
+ if (error)
+ return error;
inode = child->d_inode;
- if (unlikely(!inode))
- goto out_err;
- if (!(open_flag & O_EXCL)) {
+ if (!(file->f_flags & O_EXCL)) {
spin_lock(&inode->i_lock);
inode->i_state |= I_LINKABLE;
spin_unlock(&inode->i_lock);
}
ima_post_create_tmpfile(mnt_userns, inode);
- return child;
-
-out_err:
- dput(child);
- return ERR_PTR(error);
+ return 0;
}
/**
@@ -3641,25 +3640,15 @@ struct file *tmpfile_open(struct user_namespace *mnt_userns,
{
struct file *file;
int error;
- struct path path = { .mnt = parentpath->mnt };
-
- path.dentry = vfs_tmpfile(mnt_userns, parentpath->dentry, mode, open_flag);
- if (IS_ERR(path.dentry))
- return ERR_CAST(path.dentry);
-
- error = may_open(mnt_userns, &path, 0, open_flag);
- file = ERR_PTR(error);
- if (error)
- goto out_dput;
-
- /*
- * This relies on the "noaccount" property of fake open, otherwise
- * equivalent to dentry_open().
- */
- file = open_with_fake_path(&path, open_flag, d_inode(path.dentry), cred);
-out_dput:
- dput(path.dentry);
+ file = alloc_empty_file_noaccount(open_flag, cred);
+ if (!IS_ERR(file)) {
+ error = vfs_tmpfile(mnt_userns, parentpath, file, mode);
+ if (error) {
+ fput(file);
+ file = ERR_PTR(error);
+ }
+ }
return file;
}
EXPORT_SYMBOL(tmpfile_open);
@@ -3669,26 +3658,20 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
struct file *file)
{
struct user_namespace *mnt_userns;
- struct dentry *child;
struct path path;
int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path);
+
if (unlikely(error))
return error;
error = mnt_want_write(path.mnt);
if (unlikely(error))
goto out;
mnt_userns = mnt_user_ns(path.mnt);
- child = vfs_tmpfile(mnt_userns, path.dentry, op->mode, op->open_flag);
- error = PTR_ERR(child);
- if (IS_ERR(child))
+ error = vfs_tmpfile(mnt_userns, &path, file, op->mode);
+ if (error)
goto out2;
- dput(path.dentry);
- path.dentry = child;
- audit_inode(nd->name, child, 0);
+ audit_inode(nd->name, file->f_path.dentry, 0);
/* Don't check for other permissions, the inode was just created */
- error = may_open(mnt_userns, &path, 0, op->open_flag);
- if (!error)
- error = vfs_open(&path, file);
out2:
mnt_drop_write(path.mnt);
out:
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a445da4842e0..f0d17eefb966 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2780,6 +2780,15 @@ extern int finish_open(struct file *file, struct dentry *dentry,
int (*open)(struct inode *, struct file *));
extern int finish_no_open(struct file *file, struct dentry *dentry);
+/* Helper for the simple case when original dentry is used */
+static inline int finish_open_simple(struct file *file, int error)
+{
+ if (error)
+ return error;
+
+ return finish_open(file, file->f_path.dentry, NULL);
+}
+
/* fs/dcache.c */
extern void __init vfs_caches_init_early(void);
extern void __init vfs_caches_init(void);
--
2.37.3
