/tmp/. has the sticky bit set (+1000), so renaming any files in there is not allowed for anyone but that particular inode's owner user (or UID 0, of course). If

/tmp/. has the sticky bit set (+1000), so renaming any files in there is not allowed for anyone but that particular inode's owner user (or UID 0, of course). If your socket directory with important UNIX domain socket inodes isn't similarly protected, that's a problem.