diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2013-06-11 08:34:36 +0400 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2019-05-02 15:47:46 +0200 |
| commit | 2b79e6c7c439e83b9f5aa78357fafa19d45dbc05 (patch) | |
| tree | 58b39ccf3c6169483b263c7081736cf2e7eaba2f /fs | |
| parent | 59ea0dff75365932014b736b58afd3b425e2a9b5 (diff) | |
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
Change-Id: I5e28485680c3320cd0fccc0ba1bea8b963fca7fe
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/inode.c | 4 | ||||
| -rw-r--r-- | fs/namei.c | 16 |
2 files changed, 17 insertions, 3 deletions
diff --git a/fs/inode.c b/fs/inode.c index c0fdbbaba..dc7a0eca8 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -337,8 +337,10 @@ EXPORT_SYMBOL(set_nlink); */ void inc_nlink(struct inode *inode) { - if (WARN_ON(inode->i_nlink == 0)) + if (unlikely(inode->i_nlink == 0)) { + WARN_ON(!(inode->i_state & I_LINKABLE)); atomic_long_dec(&inode->i_sb->s_remove_count); + } inode->__i_nlink++; } diff --git a/fs/namei.c b/fs/namei.c index ca698adea..36728a45b 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3045,8 +3045,14 @@ static int do_tmpfile(int dfd, struct filename *pathname, 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: @@ -3760,12 +3766,18 @@ int vfs_link2(struct vfsmount *mnt, struct dentry *old_dentry, struct inode *dir 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); |