[src/trunk]: src/common/lib/libc/gmon fix infinite recursion through thr_gets...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e082155c5348
branches:  trunk
changeset: 343837:e082155c5348
user:      christos <christos%NetBSD.org@localhost>
date:      Sun Feb 28 02:56:39 2016 +0000

description:
fix infinite recursion through thr_getspecific

diffstat:

 common/lib/libc/gmon/mcount.c |  9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diffs (36 lines):

diff -r 499b37380ab5 -r e082155c5348 common/lib/libc/gmon/mcount.c
--- a/common/lib/libc/gmon/mcount.c     Sat Feb 27 23:51:34 2016 +0000
+++ b/common/lib/libc/gmon/mcount.c     Sun Feb 28 02:56:39 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mcount.c,v 1.12 2016/01/11 01:57:12 christos Exp $     */
+/*     $NetBSD: mcount.c,v 1.13 2016/02/28 02:56:39 christos Exp $     */
 
 /*
  * Copyright (c) 2003, 2004 Wasabi Systems, Inc.
@@ -76,7 +76,7 @@
 #if 0
 static char sccsid[] = "@(#)mcount.c   8.1 (Berkeley) 6/4/93";
 #else
-__RCSID("$NetBSD: mcount.c,v 1.12 2016/01/11 01:57:12 christos Exp $");
+__RCSID("$NetBSD: mcount.c,v 1.13 2016/02/28 02:56:39 christos Exp $");
 #endif
 #endif
 
@@ -145,12 +145,17 @@
 
 #if defined(_REENTRANT) && !defined(_KERNEL)
        if (__isthreaded) {
+               /* prevent re-entry via thr_getspecific */
+               if (_gmonparam.state != GMON_PROF_ON)
+                       return;
+               _gmonparam.state = GMON_PROF_BUSY;
                p = thr_getspecific(_gmonkey);
                if (p == NULL) {
                        /* Prevent recursive calls while allocating */
                        thr_setspecific(_gmonkey, &_gmondummy);
                        p = _m_gmon_alloc();
                }
+               _gmonparam.state = GMON_PROF_ON;
        } else
 #endif
                p = &_gmonparam;