cvs commit: src/sys/kern kern_sysctl.c

[Don Lewis]

On  5 Oct, Bruce M Simpson wrote:
> bms         2003/10/05 02:37:47 PDT
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/kern             kern_sysctl.c 
>   Log:
>   Fix a security problem in sysctl() the long way round.
>   
>   Use pre-emption detection to avoid the need for wiring a userland buffer
>   when copying opaque data structures.

In the SMP case the data can change even without pre-emption.  There
have been a number of discussions (arch@, smp@, arch-handbook, etc.)
about adding a mutex parameter to the sysctl API.  Someone even
submitted a PR with a patch a few months ago (kern/54439), which I had
hoped to review but never found the time to.