[PATCH 4.5 002/101] decnet: Do not build routes to devices without decnet private data.

From: Greg Kroah-Hartman
Date: Mon May 16 2016 - 21:47:55 EST


4.5-stable review patch. If anyone has any objections, please let me know.

------------------

From: "David S. Miller" <davem@xxxxxxxxxxxxx>

[ Upstream commit a36a0d4008488fa545c74445d69eaf56377d5d4e ]

In particular, make sure we check for decnet private presence
for loopback devices.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/decnet/dn_route.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -1034,10 +1034,13 @@ source_ok:
if (!fld.daddr) {
fld.daddr = fld.saddr;

- err = -EADDRNOTAVAIL;
if (dev_out)
dev_put(dev_out);
+ err = -EINVAL;
dev_out = init_net.loopback_dev;
+ if (!dev_out->dn_ptr)
+ goto out;
+ err = -EADDRNOTAVAIL;
dev_hold(dev_out);
if (!fld.daddr) {
fld.daddr =
@@ -1110,6 +1113,8 @@ source_ok:
if (dev_out == NULL)
goto out;
dn_db = rcu_dereference_raw(dev_out->dn_ptr);
+ if (!dn_db)
+ goto e_inval;
/* Possible improvement - check all devices for local addr */
if (dn_dev_islocal(dev_out, fld.daddr)) {
dev_put(dev_out);
@@ -1151,6 +1156,8 @@ select_source:
dev_put(dev_out);
dev_out = init_net.loopback_dev;
dev_hold(dev_out);
+ if (!dev_out->dn_ptr)
+ goto e_inval;
fld.flowidn_oif = dev_out->ifindex;
if (res.fi)
dn_fib_info_put(res.fi);