From 04e384140c6e1dd10e5ea85cd99766317ae122f3 Mon Sep 17 00:00:00 2001 From: mjg Date: Thu, 7 Jan 2016 12:08:15 +0000 Subject: MFC r292440: proc: fix a race which could result in dereference of bad p_pgrp pointer on fork During fork p_starcopy - p_endcopy area of a process is populated with bcopy with only proc lock held. Another forking thread can find such a process and proceed to access p_pgrp included in said area. Fix the problem by moving the field outside. It is being properly assigned later. --- sys/kern/kern_proc.c | 1 + 1 file changed, 1 insertion(+) (limited to 'sys/kern') diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c index e051e3e..ac0152a 100644 --- a/sys/kern/kern_proc.c +++ b/sys/kern/kern_proc.c @@ -234,6 +234,7 @@ proc_init(void *mem, int size, int flags) TAILQ_INIT(&p->p_threads); /* all threads in proc */ EVENTHANDLER_INVOKE(process_init, p); p->p_stats = pstats_alloc(); + p->p_pgrp = NULL; SDT_PROBE3(proc, kernel, init, return, p, size, flags); return (0); } -- cgit v1.1