Author: rwatson
Date: Fri Aug 28 21:12:38 2009
New Revision: 196631
URL: http://svn.freebsd.org/changeset/base/196631
Log:
Merge r196553 from head to stable/8:
Break out allocation of new ifindex values from if_alloc() and if_vmove(),
and centralize in a single function ifindex_alloc(). Assert the
IFNET_WLOCK, and add missing IFNET_WLOCK in if_alloc(). This does not
close all known races in this code.
Reviewed by: bz
Approved by: re (kib)
Modified:
stable/8/sys/ (props changed)
stable/8/sys/amd64/include/xen/ (props changed)
stable/8/sys/cddl/contrib/opensolaris/ (props changed)
stable/8/sys/contrib/dev/acpica/ (props changed)
stable/8/sys/contrib/pf/ (props changed)
stable/8/sys/dev/xen/xenpci/ (props changed)
stable/8/sys/net/if.c
Modified: stable/8/sys/net/if.c
==============================================================================
--- stable/8/sys/net/if.c Fri Aug 28 21:10:26 2009 (r196630)
+++ stable/8/sys/net/if.c Fri Aug 28 21:12:38 2009 (r196631)
@@ -223,6 +223,37 @@ ifnet_byindex_ref(u_short idx)
return (ifp);
}
+/*
+ * Allocate an ifindex array entry; return 0 on success or an error on
+ * failure.
+ */
+static int
+ifindex_alloc(u_short *idxp)
+{
+ u_short idx;
+
+ IFNET_WLOCK_ASSERT();
+
+ /*
+ * Try to find an empty slot below if_index. If we fail, take the
+ * next slot.
+ */
+ for (idx = 1; idx <= V_if_index; idx++) {
+ if (ifnet_byindex_locked(idx) == NULL)
+ break;
+ }
+
+ /* Catch if_index overflow. */
+ if (idx < 1)
+ return (ENOSPC);
+ if (idx > V_if_index)
+ V_if_index = idx;
+ if (V_if_index >= V_if_indexlim)
+ if_grow();
+ *idxp = idx;
+ return (0);
+}
+
static void
ifnet_setbyindex_locked(u_short idx, struct ifnet *ifp)
{
@@ -335,32 +366,19 @@ struct ifnet *
if_alloc(u_char type)
{
struct ifnet *ifp;
+ u_short idx;
ifp = malloc(sizeof(struct ifnet), M_IFNET, M_WAITOK|M_ZERO);
-
- /*
- * Try to find an empty slot below if_index. If we fail, take
- * the next slot.
- *
- * XXX: should be locked!
- */
- for (ifp->if_index = 1; ifp->if_index <= V_if_index; ifp->if_index++) {
- if (ifnet_byindex(ifp->if_index) == NULL)
- break;
- }
- /* Catch if_index overflow. */
- if (ifp->if_index < 1) {
+ IFNET_WLOCK();
+ if (ifindex_alloc(&idx) != 0) {
+ IFNET_WUNLOCK();
free(ifp, M_IFNET);
return (NULL);
}
- if (ifp->if_index > V_if_index)
- V_if_index = ifp->if_index;
- if (V_if_index >= V_if_indexlim)
- if_grow();
-
+ IFNET_WUNLOCK();
+ ifp->if_index = idx;
ifp->if_type = type;
ifp->if_alloctype = type;
-
if (if_com_alloc[type] != NULL) {
ifp->if_l2com = if_com_alloc[type](type, ifp);
if (ifp->if_l2com == NULL) {
@@ -882,6 +900,7 @@ if_detach_internal(struct ifnet *ifp, in
void
if_vmove(struct ifnet *ifp, struct vnet *new_vnet)
{
+ u_short idx;
/*
* Detach from current vnet, but preserve LLADDR info, do not
@@ -907,23 +926,12 @@ if_vmove(struct ifnet *ifp, struct vnet
*/
CURVNET_SET_QUIET(new_vnet);
- /*
- * Try to find an empty slot below if_index. If we fail, take
- * the next slot.
- */
IFNET_WLOCK();
- for (ifp->if_index = 1; ifp->if_index <= V_if_index; ifp->if_index++) {
- if (ifnet_byindex_locked(ifp->if_index) == NULL)
- break;
- }
- /* Catch if_index overflow. */
- if (ifp->if_index < 1)
+ if (ifindex_alloc(&idx) != 0) {
+ IFNET_WUNLOCK();
panic("if_index overflow");
-
- if (ifp->if_index > V_if_index)
- V_if_index = ifp->if_index;
- if (V_if_index >= V_if_indexlim)
- if_grow();
+ }
+ ifp->if_index = idx;
ifnet_setbyindex_locked(ifp->if_index, ifp);
IFNET_WUNLOCK();
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
