Re: [PATCH 2.6.27-rc5] Allow set RLIMIT_NOFILE to RLIM_INFINITY

[Andreas Schwab <schwab@suse.de>]

Adam Tkac <vonsch@gmail.com> writes:

> diff -puN kernel/sys.c~rlimit-permit-setting-rlimit_nofile-to-rlim_infinity kernel/sys.c
> --- a/kernel/sys.c~rlimit-permit-setting-rlimit_nofile-to-rlim_infinity
> +++ a/kernel/sys.c
> @@ -1532,8 +1532,14 @@ asmlinkage long sys_setrlimit(unsigned i
>  	if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
>  	    !capable(CAP_SYS_RESOURCE))
>  		return -EPERM;
> -	if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open)
> -		return -EPERM;
> +	if (resource == RLIMIT_NOFILE) {
> +		if (new_rlim.rlim_max == RLIM_INFINITY)
> +			new_rlim.rlim_max = sysctl_nr_open;
> +		if (new_rlim.rlim_cur == RLIM_INFINITY)
> +			new_rlim.rlim_cur = sysctl_nr_open;
> +		if (new_rlim.rlim_max > sysctl_nr_open)
> +			return -EPERM;

This makes it possible to set cur > nr_open (when max = INF but nr_open
< cur < INF).  You need to check that cur <= max after adjustment.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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