Re: PR/53998 CVS commit: src/sys/kern

[christos%zoulas.com@localhost (Christos Zoulas)]

The following reply was made to PR kern/53998; it has been noted by GNATS.

From: christos%zoulas.com@localhost (Christos Zoulas)
To: gnats-bugs%NetBSD.org@localhost, kern-bug-people%netbsd.org@localhost, 
	gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, 
	joel.bertrand%systella.fr@localhost
Cc: 
Subject: Re: PR/53998 CVS commit: src/sys/kern
Date: Sat, 23 Feb 2019 23:58:56 -0500

 On Feb 23,  6:55pm, joel.bertrand%systella.fr@localhost (=?UTF-8?Q?BERTRAND_Jo=c3=abl?=) wrote:
 -- Subject: Re: PR/53998 CVS commit: src/sys/kern
 
 The problem is that p_nsems is zeroed out on fork so we end up with negative
 counts when we close on the child (which are interpreted as overflow). The
 following patch moves p_nsems to the copy part of struct proc.
 
 christos
 
 Index: proc.h
 ===================================================================
 RCS file: /cvsroot/src/sys/sys/proc.h,v
 retrieving revision 1.350
 diff -u -p -u -r1.350 proc.h
 --- proc.h	5 Dec 2018 18:16:51 -0000	1.350
 +++ proc.h	24 Feb 2019 04:56:30 -0000
 @@ -316,7 +316,6 @@ struct proc {
  	pid_t 		p_vfpid_done;	/* :: vforked done pid */
  	lwpid_t		p_lwp_created;	/* :: lwp created */
  	lwpid_t		p_lwp_exited;	/* :: lwp exited */
 -	u_int		p_nsems;	/* Count of semaphores */
  	char		*p_path;	/* :: full pathname of executable */
  
  /*
 @@ -338,7 +337,7 @@ struct proc {
  
  	vaddr_t		p_psstrp;	/* :: address of process's ps_strings */
  	u_int		p_pax;		/* :: PAX flags */
 -
 +	u_int		p_nsems;	/* Count of semaphores */
  	int		p_xexit;	/* p: exit code */
  /*
   * End area that is copied on creation