diff options
| author | Ziyang Xuan <william.xuanziyang@huawei.com> | 2021-11-02 10:12:18 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-17 09:48:47 +0100 |
| commit | 700602b662d7eaa816b1a3cb0abe7a85de358fd4 (patch) | |
| tree | 4cc0c10eff437b2d53ef6b19211e4a50524523e3 /net | |
| parent | 98e0ab88f43515b78d0e5ccdc364587dba1493b3 (diff) | |
net: vlan: fix a UAF in vlan_dev_real_dev()
[ Upstream commit 563bcbae3ba233c275c244bfce2efe12938f5363 ]
The real_dev of a vlan net_device may be freed after
unregister_vlan_dev(). Access the real_dev continually by
vlan_dev_real_dev() will trigger the UAF problem for the
real_dev like following:
==================================================================
BUG: KASAN: use-after-free in vlan_dev_real_dev+0xf9/0x120
Call Trace:
kasan_report.cold+0x83/0xdf
vlan_dev_real_dev+0xf9/0x120
is_eth_port_of_netdev_filter.part.0+0xb1/0x2c0
is_eth_port_of_netdev_filter+0x28/0x40
ib_enum_roce_netdev+0x1a3/0x300
ib_enum_all_roce_netdevs+0xc7/0x140
netdevice_event_work_handler+0x9d/0x210
...
Freed by task 9288:
kasan_save_stack+0x1b/0x40
kasan_set_track+0x1c/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0xfc/0x130
slab_free_freelist_hook+0xdd/0x240
kfree+0xe4/0x690
kvfree+0x42/0x50
device_release+0x9f/0x240
kobject_put+0x1c8/0x530
put_device+0x1b/0x30
free_netdev+0x370/0x540
ppp_destroy_interface+0x313/0x3d0
...
Move the put_device(real_dev) to vlan_dev_free(). Ensure
real_dev not be freed before vlan_dev unregistered.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+e4df4e1389e28972e955@syzkaller.appspotmail.com
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/8021q/vlan.c | 3 | ||||
| -rw-r--r-- | net/8021q/vlan_dev.c | 3 |
2 files changed, 3 insertions, 3 deletions
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c index 3f47abf9ef4a..cd7c0429cddf 100644 --- a/net/8021q/vlan.c +++ b/net/8021q/vlan.c @@ -116,9 +116,6 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head) } vlan_vid_del(real_dev, vlan->vlan_proto, vlan_id); - - /* Get rid of the vlan's reference to real_dev */ - dev_put(real_dev); } int vlan_check_real_dev(struct net_device *real_dev, diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c index 2a78da4072de..415a29d42cdf 100644 --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -790,6 +790,9 @@ static void vlan_dev_free(struct net_device *dev) free_percpu(vlan->vlan_pcpu_stats); vlan->vlan_pcpu_stats = NULL; + + /* Get rid of the vlan's reference to real_dev */ + dev_put(vlan->real_dev); } void vlan_setup(struct net_device *dev) |