[src/trunk]: src/sys make sure every m_aux will be freed.

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

details:   https://anonhg.NetBSD.org/src/rev/1f270dfa6e32
branches:  trunk
changeset: 499222:1f270dfa6e32
user:      itojun <itojun%NetBSD.org@localhost>
date:      Tue Nov 14 20:05:28 2000 +0000

description:
make sure every m_aux will be freed.
there are direct use of MFREE() from sys/kern.
(we experienced no memory leak so far, but if we use m_aux for other purposes,
we will need this change)

diffstat:

 sys/kern/uipc_mbuf.c |   6 +-----
 sys/sys/mbuf.h       |  10 +++++++++-
 2 files changed, 10 insertions(+), 6 deletions(-)

diffs (48 lines):

diff -r ae4f4b67fa9a -r 1f270dfa6e32 sys/kern/uipc_mbuf.c
--- a/sys/kern/uipc_mbuf.c      Tue Nov 14 19:52:04 2000 +0000
+++ b/sys/kern/uipc_mbuf.c      Tue Nov 14 20:05:28 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_mbuf.c,v 1.50 2000/08/18 16:19:22 itojun Exp $    */
+/*     $NetBSD: uipc_mbuf.c,v 1.51 2000/11/14 20:05:28 itojun Exp $    */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -347,10 +347,6 @@
 
        if (m == NULL)
                return;
-       if ((m->m_flags & M_PKTHDR) != 0 && m->m_pkthdr.aux) {
-               m_freem(m->m_pkthdr.aux);
-               m->m_pkthdr.aux = NULL;
-       }
        do {
                MFREE(m, n);
                m = n;
diff -r ae4f4b67fa9a -r 1f270dfa6e32 sys/sys/mbuf.h
--- a/sys/sys/mbuf.h    Tue Nov 14 19:52:04 2000 +0000
+++ b/sys/sys/mbuf.h    Tue Nov 14 20:05:28 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mbuf.h,v 1.53 2000/08/18 16:19:23 itojun Exp $ */
+/*     $NetBSD: mbuf.h,v 1.54 2000/11/14 20:05:28 itojun Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1999 The NetBSD Foundation, Inc.
@@ -395,10 +395,18 @@
  * MFREE(struct mbuf *m, struct mbuf *n)
  * Free a single mbuf and associated external storage.
  * Place the successor, if any, in n.
+ *
+ * we do need to check non-first mbuf for m_aux, since some of existing
+ * code does not call M_PREPEND properly.
+ * (example: call to bpf_mtap from drivers)
  */
 #define        MFREE(m, n) \
        MBUFLOCK( \
                mbstat.m_mtypes[(m)->m_type]--; \
+               if (((m)->m_flags & M_PKTHDR) != 0 && (m)->m_pkthdr.aux) { \
+                       m_freem((m)->m_pkthdr.aux); \
+                       (m)->m_pkthdr.aux = NULL; \
+               } \
                if ((m)->m_flags & M_EXT) { \
                        _MEXTREMOVE((m)); \
                } \