->ndo_get_iflink() is useful for finding lower interface.
Test commands:
ip link add dummy0 type dummy
ip link add vw1 link dummy0 type virt_wifi
ip link show vw1
Before:
9: vw1: <BROADCAST,MULTICAST> ...
After:
9: vw1@dummy0: <BROADCAST,MULTICAST> ...
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Link: https://lore.kernel.org/r/20200305090636.28221-1-ap420073@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When virt_wifi interface is created, virt_wifi_newlink() is called and
it calls register_netdevice().
if register_netdevice() fails, it internally would call
->priv_destructor(), which is virt_wifi_net_device_destructor() and
it frees netdev. but virt_wifi_newlink() still use netdev.
So, use-after-free would occur in virt_wifi_newlink().
Test commands:
ip link add dummy0 type dummy
modprobe bonding
ip link add bonding_masters link dummy0 type virt_wifi
Splat looks like:
[ 202.220554] BUG: KASAN: use-after-free in virt_wifi_newlink+0x88b/0x9a0 [virt_wifi]
[ 202.221659] Read of size 8 at addr ffff888061629cb8 by task ip/852
[ 202.222896] CPU: 1 PID: 852 Comm: ip Not tainted 5.4.0-rc5 #3
[ 202.223765] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 202.225073] Call Trace:
[ 202.225532] dump_stack+0x7c/0xbb
[ 202.226869] print_address_description.constprop.5+0x1be/0x360
[ 202.229362] __kasan_report+0x12a/0x16f
[ 202.230714] kasan_report+0xe/0x20
[ 202.232595] virt_wifi_newlink+0x88b/0x9a0 [virt_wifi]
[ 202.233370] __rtnl_newlink+0xb9f/0x11b0
[ 202.244909] rtnl_newlink+0x65/0x90
[ ... ]
Cc: stable@vger.kernel.org
Fixes: c7cdba31ed ("mac80211-next: rtnetlink wifi simulation device")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Link: https://lore.kernel.org/r/20191121122645.9355-1-ap420073@gmail.com
[trim stack dump a bit]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This makes boot uniformly boottime and tai uniformly clocktai, to
address the remaining oversights.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lkml.kernel.org/r/20190621203249.3909-2-Jason@zx2c4.com
REGULATORY_WIPHY_SELF_MANAGED as set here breaks NL80211_CMD_GET_REG,
because it expects the wiphy to do regulatory management. Since
virt_wifi does not do regulatory management, this triggers a WARN_ON in
NL80211_CMD_GET_REG and fails the netlink command.
Removing REGULATORY_WIPHY_SELF_MANAGED fixes the problem and the virtual
wireless network continues to work.
Signed-off-by: Cody Schuffelen <schuffelen@google.com>
Acked-by: Alistair Strachan <astrachan@google.com>
Acked-by: Greg Hartman <ghartman@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Merge net-next so that we get the changes from net, which would
otherwise conflict with the NLA_POLICY_NESTED/_ARRAY changes.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/net/wireless/virt_wifi.c: In function 'virt_wifi_net_device_stop':
drivers/net/wireless/virt_wifi.c:432:31: warning:
variable 'w_priv' set but not used [-Wunused-but-set-variable]
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Fixes: c7cdba31ed ("mac80211-next: rtnetlink wifi simulation device")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This device takes over an existing network device and produces a
new one that appears like a wireless connection, returning enough canned
responses to nl80211 to satisfy a standard connection manager. If
necessary, it can also be set up one step removed from an existing
network device, such as through a vlan/80211Q or macvlan connection to
not disrupt the existing network interface.
To use it to wrap a bare ethernet connection:
ip link add link eth0 name wlan0 type virt_wifi
You may have to rename or otherwise hide the eth0 from your connection
manager, as the original network link will become unusuable and only
the wireless wrapper will be functional. This can also be combined with
vlan or macvlan links on top of eth0 to share the network between
distinct links, but that requires support outside the machine for
accepting vlan-tagged packets or packets from multiple MAC addresses.
This is being used for Google's Remote Android Virtual Device project,
which runs Android devices in virtual machines. The standard network
interfaces provided inside the virtual machines are all ethernet.
However, Android is not interested in ethernet devices and would rather
connect to a wireless interface. This patch allows the virtual machine
guest to treat one of its network connections as wireless rather than
ethernet, satisfying Android's network connection requirements.
We believe this is a generally useful driver for simulating wireless
network connections in other environments where a wireless connection is
desired by some userspace process but is not available.
This is distinct from other testing efforts such as mac80211_hwsim by
being a cfg80211 device instead of mac80211 device, allowing straight
pass-through on the data plane instead of forcing packaging of ethernet
data into mac80211 frames.
Signed-off-by: A. Cody Schuffelen <schuffelen@google.com>
Acked-by: Alistair Strachan <astrachan@google.com>
Acked-by: Greg Hartman <ghartman@google.com>
Acked-by: Tristan Muntsinger <muntsinger@google.com>
[make it a tristate]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>