Re: [PATCH 1/2] coredump: fix race condition between connect and

[Laura Brehm <laurajfbrehm@gmail.com>]

> kernel_connect()
> -> sock->ops->connect::unix_stream_connect()
>   -> prepare_peercred()
>      -> pidfs_register_pid()

Ah, thank you! I initially ran into this while working from an older
tree that had had the coredump-socket series cherry-picked into it,
but it was missing Commit fd0a109a0f6b7524543d17520da92a44a9f5343c
("net, pidfs: prepare for handing out pidfds for reaped 
sk->sk_peer_pid").

My tree instead had:
    static void init_peercred(struct sock *sk)
    {
	    sk->sk_peer_pid = get_pid(task_tgid(current));
	    sk->sk_peer_cred = get_current_cred();
    }

I switched over to the main tree when preparing patches, but missed
that the issue was not present there. 

> Honestly curious: is that something you actually observed or that you
> think may happen or that an some coding assistant thinks might happen?

No coding assistants (not a fan), but I understand the question. I
maintain some other large projects and we get a few inane patches
too. I usually try my best to avoid making patches such as these
without some amount of double checking if I'm addressing a real issue,
but I did run into the issue I described (about half the time,
depending on how fast the coredump server ran) in my tree, and I
forgot to repro after switching trees.

Apologies for the inconvenience, and for the understanding/quick
replies!