- When disabling ktracing on a process, free any pending requests that

  may be left.  This fixes a memory leak that can occur when tracing is
  disabled on a process via disabling tracing of a specific file (or if
  an I/O error occurs with the tracefile) if the process's next system
  call is exit().  The trace disabling code clears p_traceflag, so exit1()
  doesn't do any KTRACE-related cleanup leading to the leak.  I chose to
  make the free'ing of pending records synchronous rather than patching
  exit1().
- Move KTRACE-specific logic out of kern_(exec|exit|fork).c and into
  kern_ktrace.c instead.  Make ktrace_mtx private to kern_ktrace.c as a
  result.

MFC after:	1 month

1 files changed, 1 insertions, 15 deletions

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index da2c415..126c668 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -645,21 +645,7 @@ again:
 	callout_init(&p2->p_itcallout, CALLOUT_MPSAFE);
 
 #ifdef KTRACE
-	/*
-	 * Copy traceflag and tracefile if enabled.
-	 */
-	mtx_lock(&ktrace_mtx);
-	KASSERT(p2->p_tracevp == NULL, ("new process has a ktrace vnode"));
-	if (p1->p_traceflag & KTRFAC_INHERIT) {
-		p2->p_traceflag = p1->p_traceflag;
-		if ((p2->p_tracevp = p1->p_tracevp) != NULL) {
-			VREF(p2->p_tracevp);
-			KASSERT(p1->p_tracecred != NULL,
-			    ("ktrace vnode with no cred"));
-			p2->p_tracecred = crhold(p1->p_tracecred);
-		}
-	}
-	mtx_unlock(&ktrace_mtx);
+	ktrprocfork(p1, p2);
 #endif
 
 	/*