kernel/drivers/net/wireless/virtual/virt_wifi.c, branch 0x221E-v0.0.1-v6.19

wifi: virt_wifi: remove SET_NETDEV_DEV to avoid use-after-free

2026-04-11T12:29:58Z

commit 789b06f9f39cdc7e895bdab2c034e39c41c8f8d6 upstream. Currently we execute `SET_NETDEV_DEV(dev, &priv->lowerdev->dev)` for the virt_wifi net devices. However, unregistering a virt_wifi device in netdev_run_todo() can happen together with the device referenced by SET_NETDEV_DEV(). It can result in use-after-free during the ethtool operations performed on a virt_wifi device that is currently being unregistered. Such a net device can have the `dev.parent` field pointing to the freed memory, but ethnl_ops_begin() calls `pm_runtime_get_sync(dev->dev.parent)`. Let's remove SET_NETDEV_DEV for virt_wifi to avoid bugs like this: ================================================================== BUG: KASAN: slab-use-after-free in __pm_runtime_resume+0xe2/0xf0 Read of size 2 at addr ffff88810cfc46f8 by task pm/606 Call Trace: dump_stack_lvl+0x4d/0x70 print_report+0x170/0x4f3 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 kasan_report+0xda/0x110 ? __pm_runtime_resume+0xe2/0xf0 ? __pm_runtime_resume+0xe2/0xf0 __pm_runtime_resume+0xe2/0xf0 ethnl_ops_begin+0x49/0x270 ethnl_set_features+0x23c/0xab0 ? __pfx_ethnl_set_features+0x10/0x10 ? kvm_sched_clock_read+0x11/0x20 ? local_clock_noinstr+0xf/0xf0 ? local_clock+0x10/0x30 ? kasan_save_track+0x25/0x60 ? __kasan_kmalloc+0x7f/0x90 ? genl_family_rcv_msg_attrs_parse.isra.0+0x150/0x2c0 genl_family_rcv_msg_doit+0x1e7/0x2c0 ? __pfx_genl_family_rcv_msg_doit+0x10/0x10 ? __pfx_cred_has_capability.isra.0+0x10/0x10 ? stack_trace_save+0x8e/0xc0 genl_rcv_msg+0x411/0x660 ? __pfx_genl_rcv_msg+0x10/0x10 ? __pfx_ethnl_set_features+0x10/0x10 netlink_rcv_skb+0x121/0x380 ? __pfx_genl_rcv_msg+0x10/0x10 ? __pfx_netlink_rcv_skb+0x10/0x10 ? __pfx_down_read+0x10/0x10 genl_rcv+0x23/0x30 netlink_unicast+0x60f/0x830 ? __pfx_netlink_unicast+0x10/0x10 ? __pfx___alloc_skb+0x10/0x10 netlink_sendmsg+0x6ea/0xbc0 ? __pfx_netlink_sendmsg+0x10/0x10 ? __futex_queue+0x10b/0x1f0 ____sys_sendmsg+0x7a2/0x950 ? copy_msghdr_from_user+0x26b/0x430 ? __pfx_____sys_sendmsg+0x10/0x10 ? __pfx_copy_msghdr_from_user+0x10/0x10 ___sys_sendmsg+0xf8/0x180 ? __pfx____sys_sendmsg+0x10/0x10 ? __pfx_futex_wait+0x10/0x10 ? fdget+0x2e4/0x4a0 __sys_sendmsg+0x11f/0x1c0 ? __pfx___sys_sendmsg+0x10/0x10 do_syscall_64+0xe2/0x570 ? exc_page_fault+0x66/0xb0 entry_SYSCALL_64_after_hwframe+0x77/0x7f This fix may be combined with another one in the ethtool subsystem: https://lore.kernel.org/all/20260322075917.254874-1-alex.popov@linux.com/T/#u Fixes: d43c65b05b848e0b ("ethtool: runtime-resume netdev parent in ethnl_ops_begin") Cc: stable@vger.kernel.org Signed-off-by: Alexander Popov Acked-by: Greg Kroah-Hartman Reviewed-by: Breno Leitao Link: https://patch.msgid.link/20260324224607.374327-1-alex.popov@linux.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: virt_wifi: Fix page fault on connect

2025-09-10T13:01:07Z

This patch prevents page fault in __cfg80211_connect_result()[1] when connecting a virt_wifi device, while ensuring that virt_wifi can connect properly. [1] https://lore.kernel.org/linux-wireless/20250909063213.1055024-1-guan_yufei@163.com/ Closes: https://lore.kernel.org/linux-wireless/20250909063213.1055024-1-guan_yufei@163.com/ Signed-off-by: James Guan Link: https://patch.msgid.link/20250910111929.137049-1-guan_yufei@163.com [remove irrelevant network-manager instructions] Signed-off-by: Johannes Berg

wifi: virt_wifi: Add __nonstring annotations for unterminated strings

2025-03-12T08:48:28Z

When a character array without a terminating NUL character has a static initializer, GCC 15's -Wunterminated-string-initialization will only warn if the array lacks the "nonstring" attribute[1]. Mark the arrays with __nonstring to and correctly identify the char array as "not a C string" and thereby eliminate the warning. Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1] Signed-off-by: Kees Cook Link: https://patch.msgid.link/20250311225604.it.926-kees@kernel.org Signed-off-by: Johannes Berg

net: Use link/peer netns in newlink() of rtnl_link_ops

2025-02-21T23:28:02Z

Add two helper functions - rtnl_newlink_link_net() and rtnl_newlink_peer_net() for netns fallback logic. Peer netns falls back to link netns, and link netns falls back to source netns. Convert the use of params->net in netdevice drivers to one of the helper functions for clarity. Signed-off-by: Xiao Liang Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250219125039.18024-4-shaw.leon@gmail.com Signed-off-by: Jakub Kicinski

rtnetlink: Pack newlink() params into struct

2025-02-21T23:28:02Z

There are 4 net namespaces involved when creating links: - source netns - where the netlink socket resides, - target netns - where to put the device being created, - link netns - netns associated with the device (backend), - peer netns - netns of peer device. Currently, two nets are passed to newlink() callback - "src_net" parameter and "dev_net" (implicitly in net_device). They are set as follows, depending on netlink attributes in the request. +------------+-------------------+---------+---------+ | peer netns | IFLA_LINK_NETNSID | src_net | dev_net | +------------+-------------------+---------+---------+ | | absent | source | target | | absent +-------------------+---------+---------+ | | present | link | link | +------------+-------------------+---------+---------+ | | absent | peer | target | | present +-------------------+---------+---------+ | | present | peer | link | +------------+-------------------+---------+---------+ When IFLA_LINK_NETNSID is present, the device is created in link netns first and then moved to target netns. This has some side effects, including extra ifindex allocation, ifname validation and link events. These could be avoided if we create it in target netns from the beginning. On the other hand, the meaning of src_net parameter is ambiguous. It varies depending on how parameters are passed. It is the effective link (or peer netns) by design, but some drivers ignore it and use dev_net instead. To provide more netns context for drivers, this patch packs existing newlink() parameters, along with the source netns, link netns and peer netns, into a struct. The old "src_net" is renamed to "net" to avoid confusion with real source netns, and will be deprecated later. The use of src_net are converted to params->net trivially. Signed-off-by: Xiao Liang Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250219125039.18024-3-shaw.leon@gmail.com Signed-off-by: Jakub Kicinski

wifi: virt_wifi: don't use strlen() in const context

2024-07-09T06:49:56Z

Looks like not all compilers allow strlen(constant) as a constant, so don't do that. Instead, revert back to defining the length as the first submission had it. Fixes: b5d14b0c6716 ("wifi: virt_wifi: avoid reporting connection success with wrong SSID") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202407090934.NnR1TUbW-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202407090944.mpwLHGt9-lkp@intel.com/ Signed-off-by: Johannes Berg

wifi: virt_wifi: avoid reporting connection success with wrong SSID

2024-07-08T16:28:47Z

When user issues a connection with a different SSID than the one virt_wifi has advertised, the __cfg80211_connect_result() will trigger the warning: WARN_ON(bss_not_found). The issue is because the connection code in virt_wifi does not check the SSID from user space (it only checks the BSSID), and virt_wifi will call cfg80211_connect_result() with WLAN_STATUS_SUCCESS even if the SSID is different from the one virt_wifi has advertised. Eventually cfg80211 won't be able to find the cfg80211_bss and generate the warning. Fixed it by checking the SSID (from user space) in the connection code. Fixes: c7cdba31ed8b ("mac80211-next: rtnetlink wifi simulation device") Reported-by: syzbot+d6eb9cee2885ec06f5e3@syzkaller.appspotmail.com Signed-off-by: En-Wei Wu Link: https://patch.msgid.link/20240705023756.10954-1-en-wei.wu@canonical.com Signed-off-by: Johannes Berg

rtnetlink: prepare nla_put_iflink() to run under RCU

2024-02-26T11:46:12Z

We want to be able to run rtnl_fill_ifinfo() under RCU protection instead of RTNL in the future. This patch prepares dev_get_iflink() and nla_put_iflink() to run either with RTNL or RCU held. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

wifi: move mac80211_hwsim and virt_wifi to virtual directory

2023-03-13T13:42:14Z

To clean up drivers/net/wireless move the virtual drivers to a new virtual directory. I did consider adding CONFIG_WLAN_VENDOR_VIRTUAL like other vendors have but then dropped the idea as we are not real drivers. There should be no changes in compilation or in Kconfig options, merely moving files. The order in menuconfig is slightly changed, the virtual drivers are now last in the list. Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230227121732.8967-2-kvalo@kernel.org