Btrfs: check for read permission on src file in the clone ioctl

The existing code would have allowed you to clone a file that was
only open for writing

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Dan Rosenberg 2010-05-15 11:27:37 -04:00 committed by Chris Mason
parent 9f680ce04e
commit 5dc6416414
1 changed files with 5 additions and 0 deletions

View File

@ -1480,12 +1480,17 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
ret = -EBADF;
goto out_drop_write;
}
src = src_file->f_dentry->d_inode;
ret = -EINVAL;
if (src == inode)
goto out_fput;
/* the src must be open for reading */
if (!(src_file->f_mode & FMODE_READ))
goto out_fput;
ret = -EISDIR;
if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
goto out_fput;