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-rw-r--r--sys/conf/files1
-rw-r--r--sys/net/if.c5
-rw-r--r--sys/net/if_dead.c114
-rw-r--r--sys/net/if_var.h1
4 files changed, 121 insertions, 0 deletions
diff --git a/sys/conf/files b/sys/conf/files
index 0a997b3..68282c7 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -2152,6 +2152,7 @@ net/if_arcsubr.c optional arcnet
net/if_atmsubr.c optional atm
net/if_bridge.c optional bridge | if_bridge
net/if_clone.c standard
+net/if_dead.c standard
net/if_disc.c optional disc
net/if_edsc.c optional edsc
net/if_ef.c optional ef
diff --git a/sys/net/if.c b/sys/net/if.c
index 54cd916..f116f55 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -929,6 +929,11 @@ if_detach(struct ifnet *ifp)
if_purgemaddrs(ifp);
/*
+ * Prevent further calls into the device driver via ifnet.
+ */
+ if_dead(ifp);
+
+ /*
* Remove link ifaddr pointer and maybe decrement if_index.
* Clean up all addresses.
*/
diff --git a/sys/net/if_dead.c b/sys/net/if_dead.c
new file mode 100644
index 0000000..b28ffc2
--- /dev/null
+++ b/sys/net/if_dead.c
@@ -0,0 +1,114 @@
+/*-
+ * Copyright (c) 2009 Robert N. M. Watson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * When an interface has been detached but not yet freed, we set the various
+ * ifnet function pointers to "ifdead" versions. This prevents unexpected
+ * calls from the network stack into the device driver after if_detach() has
+ * returned.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+#include <net/if_var.h>
+
+static int
+ifdead_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa,
+ struct route *ro)
+{
+
+ m_freem(m);
+ return (ENXIO);
+}
+
+static void
+ifdead_input(struct ifnet *ifp, struct mbuf *m)
+{
+
+ m_freem(m);
+}
+
+static void
+ifdead_start(struct ifnet *ifp)
+{
+
+}
+
+static int
+ifdead_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
+{
+
+ return (ENXIO);
+}
+
+static void
+ifdead_watchdog(struct ifnet *ifp)
+{
+
+}
+
+static int
+ifdead_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
+ struct sockaddr *sa)
+{
+
+ *llsa = NULL;
+ return (ENXIO);
+}
+
+static void
+ifdead_qflush(struct ifnet *ifp)
+{
+
+}
+
+static int
+ifdead_transmit(struct ifnet *ifp, struct mbuf *m)
+{
+
+ m_freem(m);
+ return (ENXIO);
+}
+
+void
+if_dead(struct ifnet *ifp)
+{
+
+ ifp->if_output = ifdead_output;
+ ifp->if_input = ifdead_input;
+ ifp->if_start = ifdead_start;
+ ifp->if_ioctl = ifdead_ioctl;
+ ifp->if_watchdog = ifdead_watchdog;
+ ifp->if_resolvemulti = ifdead_resolvemulti;
+ ifp->if_qflush = ifdead_qflush;
+ ifp->if_transmit = ifdead_transmit;
+}
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 26b2747..4078f8f 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -753,6 +753,7 @@ int if_addmulti(struct ifnet *, struct sockaddr *, struct ifmultiaddr **);
int if_allmulti(struct ifnet *, int);
struct ifnet* if_alloc(u_char);
void if_attach(struct ifnet *);
+void if_dead(struct ifnet *);
int if_delmulti(struct ifnet *, struct sockaddr *);
void if_delmulti_ifma(struct ifmultiaddr *);
void if_detach(struct ifnet *);
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