Re: [Exim] Exim 4.40 crashes in src/daemon.c

From: "Heiko Schlichting" <exim-users@???>
>
> Exim 4.40 uses the function smtp_printf() in line 166 of src/daemon.c to
> return an 421 error message. This is a problem as smtp_printf() writes to
> the filedescriptor smtp_out which is undefined at this time as it is not
> set until line 194 of the same function. In cases the error condition
> occurs (which could happen every now and then on some heavy loaded servers
> at least on some architectures[*]) the exim master daemon crashes.

Thanks for finding this.

I believe this can happen on any architecture, under any load, if the client
sends RST on the connection prior to the getsockname() call. Maybe also if
the client just closes the connection at the right time.

David