DTrace MFC broke kldstat(2) on RELENG_7

[John Baldwin]

On Tuesday 30 September 2008 06:15:59 am Jaakko Heinonen wrote:
> 
> Hi,
> 
> I recently noticed that kldstat(8) started to dump core for me on
> RELENG_7. I traced the problem down to kldstat(2). r182231 (DTrace
> MFC) introduced a new version of kld_file_stat struct and added some
> code to support the old version of the structure in kldstat(). In the
> new code the old structure is known as kld_file_stat_1. Unfortunately
> there's a bug in this code: kldstat() copies always sizeof(struct
> kld_file_stat) of data to user space while it should copy sizeof(struct
> kld_file_stat_1) when the old struct is used.
> 
> This guy is probably suffering from this problem too:
> 
http://lists.freebsd.org/pipermail/freebsd-questions/2008-September/182896.html
> 
> I used this patch to fix the problem:
> 
> %%%
> Index: sys/kern/kern_linker.c
> ===================================================================
> --- sys/kern/kern_linker.c	(revision 183486)
> +++ sys/kern/kern_linker.c	(working copy)
> @@ -1199,7 +1199,12 @@ kldstat(struct thread *td, struct kldsta
>  
>  	td->td_retval[0] = 0;
>  
> -	return (copyout(&stat, uap->stat, sizeof(struct kld_file_stat)));
> +	if (version_num == 1)
> +		return (copyout(&stat, uap->stat,
> +		    sizeof(struct kld_file_stat_1)));
> +	else
> +		return (copyout(&stat, uap->stat,
> +		    sizeof(struct kld_file_stat)));
>  }
>  
>  int
> %%%

This is what is in HEAD and should fix it:

Index: kern_linker.c
===================================================================
--- kern_linker.c       (revision 183497)
+++ kern_linker.c       (working copy)
@@ -1199,7 +1199,7 @@

        td->td_retval[0] = 0;

-       return (copyout(&stat, uap->stat, sizeof(struct kld_file_stat)));
+       return (copyout(&stat, uap->stat, version));
 }


I will send in a request to MFC it in a second.

-- 
John Baldwin