Ubuntu
linux-goldfish package

  1. Precise (12.04)
  2. Bug #1535150
  3. Comment #1

Comment 1 for bug 1535150

Revision history for this message
Tyler Hicks (tyhicks) wrote : Re: overlayfs over fuse should refuse copy_up of files if uid/gid not mapped

I haven't verified this bug report but wanted to mention my initial thoughts on it. An inode that is setuid and world writable is a valid inode. It should remain setuid until it is written to and, at that point, the setuid bit should be stripped. This is done by file_remove_privs(), which must be called by the function assigned to the .write_iter member of a filesystem's file_operations struct.

It sounds like this is possibly not happening on inodes that are copied up by overlayfs.