From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Thu, 16 Aug 2012 01:17:43 +0000 (-0700)
Subject: kernel - Fix numerous procfs/ptrace issues (3)
X-Git-Tag: v3.0.3~8
X-Git-Url: http://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/f5e3dacfcb9647d13edda3586dd637318a18149c

kernel - Fix numerous procfs/ptrace issues (3)

* Add a safety spin-lock around adjustments to p_stops so it hopefully
  interacts better with the event processing side of things.
---

diff --git a/sys/vfs/procfs/procfs_vnops.c b/sys/vfs/procfs/procfs_vnops.c
index f3b79bd..8974479 100644
--- a/sys/vfs/procfs/procfs_vnops.c
+++ b/sys/vfs/procfs/procfs_vnops.c
@@ -302,10 +302,14 @@ procfs_ioctl(struct vop_ioctl_args *ap)
 
 	switch (ap->a_command) {
 	case PIOCBIS:
+	  spin_lock(&procp->p_spin);
 	  procp->p_stops |= *(unsigned int*)ap->a_data;
+	  spin_unlock(&procp->p_spin);
 	  break;
 	case PIOCBIC:
+	  spin_lock(&procp->p_spin);
 	  procp->p_stops &= ~*(unsigned int*)ap->a_data;
+	  spin_unlock(&procp->p_spin);
 	  break;
 	case PIOCSFL:
 	  /*