[PATCH 4.19 08/61] net: openvswitch: do not free vport if register_netdevice() is failed.
From: Greg Kroah-Hartman
Date: Thu Jun 20 2019 - 14:10:30 EST
From: Taehee Yoo <ap420073@xxxxxxxxx>
[ Upstream commit 309b66970ee2abf721ecd0876a48940fa0b99a35 ]
In order to create an internal vport, internal_dev_create() is used and
that calls register_netdevice() internally.
If register_netdevice() fails, it calls dev->priv_destructor() to free
private data of netdev. actually, a private data of this is a vport.
Hence internal_dev_create() should not free and use a vport after failure
of register_netdevice().
Test command
ovs-dpctl add-dp bonding_masters
Splat looks like:
[ 1035.667767] kasan: GPF could be caused by NULL-ptr deref or user memory access
[ 1035.675958] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 1035.676916] CPU: 1 PID: 1028 Comm: ovs-vswitchd Tainted: G B 5.2.0-rc3+ #240
[ 1035.676916] RIP: 0010:internal_dev_create+0x2e5/0x4e0 [openvswitch]
[ 1035.676916] Code: 48 c1 ea 03 80 3c 02 00 0f 85 9f 01 00 00 4c 8b 23 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 60 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 86 01 00 00 49 8b bc 24 60 05 00 00 e8 e4 68 f4
[ 1035.713720] RSP: 0018:ffff88810dcb7578 EFLAGS: 00010206
[ 1035.713720] RAX: dffffc0000000000 RBX: ffff88810d13fe08 RCX: ffffffff84297704
[ 1035.713720] RDX: 00000000000000ac RSI: 0000000000000000 RDI: 0000000000000560
[ 1035.713720] RBP: 00000000ffffffef R08: fffffbfff0d3b881 R09: fffffbfff0d3b881
[ 1035.713720] R10: 0000000000000001 R11: fffffbfff0d3b880 R12: 0000000000000000
[ 1035.768776] R13: 0000607ee460b900 R14: ffff88810dcb7690 R15: ffff88810dcb7698
[ 1035.777709] FS: 00007f02095fc980(0000) GS:ffff88811b400000(0000) knlGS:0000000000000000
[ 1035.777709] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1035.777709] CR2: 00007ffdf01d2f28 CR3: 0000000108258000 CR4: 00000000001006e0
[ 1035.777709] Call Trace:
[ 1035.777709] ovs_vport_add+0x267/0x4f0 [openvswitch]
[ 1035.777709] new_vport+0x15/0x1e0 [openvswitch]
[ 1035.777709] ovs_vport_cmd_new+0x567/0xd10 [openvswitch]
[ 1035.777709] ? ovs_dp_cmd_dump+0x490/0x490 [openvswitch]
[ 1035.777709] ? __kmalloc+0x131/0x2e0
[ 1035.777709] ? genl_family_rcv_msg+0xa54/0x1030
[ 1035.777709] genl_family_rcv_msg+0x63a/0x1030
[ 1035.777709] ? genl_unregister_family+0x630/0x630
[ 1035.841681] ? debug_show_all_locks+0x2d0/0x2d0
[ ... ]
Fixes: cf124db566e6 ("net: Fix inconsistent teardown and release of private netdev state.")
Signed-off-by: Taehee Yoo <ap420073@xxxxxxxxx>
Reviewed-by: Greg Rose <gvrose8192@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/openvswitch/vport-internal_dev.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
--- a/net/openvswitch/vport-internal_dev.c
+++ b/net/openvswitch/vport-internal_dev.c
@@ -169,7 +169,9 @@ static struct vport *internal_dev_create
{
struct vport *vport;
struct internal_dev *internal_dev;
+ struct net_device *dev;
int err;
+ bool free_vport = true;
vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
if (IS_ERR(vport)) {
@@ -177,8 +179,9 @@ static struct vport *internal_dev_create
goto error;
}
- vport->dev = alloc_netdev(sizeof(struct internal_dev),
- parms->name, NET_NAME_USER, do_setup);
+ dev = alloc_netdev(sizeof(struct internal_dev),
+ parms->name, NET_NAME_USER, do_setup);
+ vport->dev = dev;
if (!vport->dev) {
err = -ENOMEM;
goto error_free_vport;
@@ -199,8 +202,10 @@ static struct vport *internal_dev_create
rtnl_lock();
err = register_netdevice(vport->dev);
- if (err)
+ if (err) {
+ free_vport = false;
goto error_unlock;
+ }
dev_set_promiscuity(vport->dev, 1);
rtnl_unlock();
@@ -210,11 +215,12 @@ static struct vport *internal_dev_create
error_unlock:
rtnl_unlock();
- free_percpu(vport->dev->tstats);
+ free_percpu(dev->tstats);
error_free_netdev:
- free_netdev(vport->dev);
+ free_netdev(dev);
error_free_vport:
- ovs_vport_free(vport);
+ if (free_vport)
+ ovs_vport_free(vport);
error:
return ERR_PTR(err);
}