Re: CVS commit: src/sys/kern

[Matt Thomas <matt%3am-software.com@localhost>]

On Dec 14, 2009, at 2:12 PM, Mindaugas Rasiukevicius wrote:

> Hello,
> 
>> Module Name:    src
>> Committed By:   dsl
>> Date:           Sat Dec 12 17:47:05 UTC 2009
>> 
>> Modified Files:
>>        src/sys/kern: sys_select.c
>> 
>> Log Message:
>> Bounding the 'nfds' arg to poll() at the current process limit for actual
>> open files is rather gross - the poll map isn't required to be dense.
>> Instead limit to a much larger value (1000 + dt_nfiles) so that user
>> programs cannot allocate indefinite sized blocks of kvm.
> 
> This does not look right to me.
> 
> - Where does the random value 1000 come from?  If you need a limit, POSIX
>  allows to limit up to OPEN_MAX (thus did SVR4?).
> 
> - How about truncating to fd_lastfile (plus one), instead of dt_nfiles?

you could has one each pollfd for IN, OUT, HUP so that's 3 times nfiles.