allow the temp files created by open() to be linked to
O_TMPFILE | O_CREAT => linkat() with AT_SYMLINK_FOLLOW and /proc/self/fd/<n>
as oldpath (i.e. flink()) will create a link
O_TMPFILE | O_CREAT | O_EXCL => ENOENT on attempt to link those guys
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 778e253..66998b0 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2948,8 +2948,14 @@
if (error)
goto out2;
error = open_check_o_direct(file);
- if (error)
+ if (error) {
fput(file);
+ } else if (!(op->open_flag & O_EXCL)) {
+ struct inode *inode = file_inode(file);
+ spin_lock(&inode->i_lock);
+ inode->i_state |= I_LINKABLE;
+ spin_unlock(&inode->i_lock);
+ }
out2:
mnt_drop_write(nd->path.mnt);
out:
@@ -3628,12 +3634,18 @@
mutex_lock(&inode->i_mutex);
/* Make sure we don't allow creating hardlink to an unlinked file */
- if (inode->i_nlink == 0)
+ if (inode->i_nlink == 0 && !(inode->i_state & I_LINKABLE))
error = -ENOENT;
else if (max_links && inode->i_nlink >= max_links)
error = -EMLINK;
else
error = dir->i_op->link(old_dentry, dir, new_dentry);
+
+ if (!error && (inode->i_state & I_LINKABLE)) {
+ spin_lock(&inode->i_lock);
+ inode->i_state &= ~I_LINKABLE;
+ spin_unlock(&inode->i_lock);
+ }
mutex_unlock(&inode->i_mutex);
if (!error)
fsnotify_link(dir, inode, new_dentry);
