svn commit: r189066 - head/sys/kern

[Bjoern A. Zeeb]

On Thu, 26 Feb 2009, Ed Schouten wrote:

> Author: ed
> Date: Thu Feb 26 12:12:34 2009
> New Revision: 189066
> URL: http://svn.freebsd.org/changeset/base/189066
>
> Log:
>  Remove redundant assignment of `p'.
>
>  `p' is already initialized with `td->td_proc'. Because td is always
>  curthread, it is safe to initialize it without any locks.
>
>  Found by:	LLVM's scan-build
>
> Modified:
>  head/sys/kern/subr_prf.c
>
> Modified: head/sys/kern/subr_prf.c
> ==============================================================================
> --- head/sys/kern/subr_prf.c	Thu Feb 26 12:06:46 2009	(r189065)
> +++ head/sys/kern/subr_prf.c	Thu Feb 26 12:12:34 2009	(r189066)
> @@ -137,7 +137,6 @@ uprintf(const char *fmt, ...)
> 		return (0);
>
> 	sx_slock(&proctree_lock);
> -	p = td->td_proc;
> 	PROC_LOCK(p);
> 	if ((p->p_flag & P_CONTROLT) == 0) {
> 		PROC_UNLOCK(p);


I think this one is wrong. You should probably have removed the
assignment from declaration time as we are checking for td != NULL
just above that so it could possibly be a NULL pointer deref in the
initial assigment or the NULL check is redundant.

-- 
Bjoern A. Zeeb                      The greatest risk is not taking one.