Re: [PATCH v1 net-next] Revert "af_unix: Call scm_recv() only after scm_set_cred()."

[Jiri Olsa <olsajiri@gmail.com>]

On Mon, Jun 26, 2023 at 01:58:37PM -0700, Kuniyuki Iwashima wrote:
> This reverts commit 3f5f118bb657f94641ea383c7c1b8c09a5d46ea2.
> 
> Konrad reported that desktop environment below cannot be reached after
> commit 3f5f118bb657 ("af_unix: Call scm_recv() only after scm_set_cred().")
> 
>   - postmarketOS (Alpine Linux w/ musl 1.2.4)
>   - busybox 1.36.1
>   - GNOME 44.1
>   - networkmanager 1.42.6
>   - openrc 0.47
> 
> Regarding to the warning of SO_PASSPIDFD, I'll post another patch to
> suppress it by skipping SCM_PIDFD if scm->pid == NULL in scm_pidfd_recv().
> 
> Reported-by: Konrad Dybcio <konradybcio@kernel.org>
> Link: https://lore.kernel.org/netdev/8c7f9abd-4f84-7296-2788-1e130d6304a0@kernel.org/
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>

hit the same issue, this revert fixes it for me, fwiw:

Teste-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

> ---
> To maintainers
> 
> Sorry for bothering, but can this make it to the v6.5 train to
> avoid regression reports ?
> ---
>  net/unix/af_unix.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index f2f234f0b92c..3953daa2e1d0 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -2807,7 +2807,7 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state,
>  	} while (size);
>  
>  	mutex_unlock(&u->iolock);
> -	if (state->msg && check_creds)
> +	if (state->msg)
>  		scm_recv(sock, state->msg, &scm, flags);
>  	else
>  		scm_destroy(&scm);
> -- 
> 2.30.2
>