kernel_optimize_test/net/8021q
Ziyang Xuan e04a7a84bb 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: 1da177e4c3 ("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>
2021-11-18 14:04:26 +01:00
..
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile
vlan_core.c net: vlan: suppress "failed to kill vid" warnings 2020-02-17 14:30:54 -08:00
vlan_dev.c net: vlan: fix a UAF in vlan_dev_real_dev() 2021-11-18 14:04:26 +01:00
vlan_gvrp.c
vlan_mvrp.c
vlan_netlink.c vlan: vlan_changelink() should propagate errors 2020-01-07 13:35:14 -08:00
vlan.c net: vlan: fix a UAF in vlan_dev_real_dev() 2021-11-18 14:04:26 +01:00
vlan.h net: vlan: Avoid using BUG() in vlan_proto_idx() 2020-09-25 14:12:18 -07:00
vlanproc.c
vlanproc.h