From 309b66970ee2abf721ecd0876a48940fa0b99a35 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Sun, 9 Jun 2019 23:26:21 +0900 Subject: [PATCH] net: openvswitch: do not free vport if register_netdevice() is failed. 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 Reviewed-by: Greg Rose Signed-off-by: David S. Miller --- net/openvswitch/vport-internal_dev.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/net/openvswitch/vport-internal_dev.c b/net/openvswitch/vport-internal_dev.c index 26f71cbf7527..5993405c25c1 100644 --- a/net/openvswitch/vport-internal_dev.c +++ b/net/openvswitch/vport-internal_dev.c @@ -170,7 +170,9 @@ static struct vport *internal_dev_create(const struct vport_parms *parms) { 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)) { @@ -178,8 +180,9 @@ static struct vport *internal_dev_create(const struct vport_parms *parms) 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; @@ -200,8 +203,10 @@ static struct vport *internal_dev_create(const struct vport_parms *parms) 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(); @@ -211,11 +216,12 @@ static struct vport *internal_dev_create(const struct vport_parms *parms) 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); } -- 2.30.2