From nobody Fri Apr 3 02:58:17 2026 Received: from mail-lf1-f45.google.com (mail-lf1-f45.google.com [209.85.167.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5FF0A38C43C for ; Tue, 24 Mar 2026 22:46:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.45 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774392395; cv=none; b=Wjie8/gJlV5V6M39UCK0UhG73qDKWskEJTViWDMDSaTTYW69KVMGtNxTHs+T3IJeIXGFLsVewr7u7QqfRrZB0JHQAV23fpFVC6uZqE/bZaBZEYbhZIJLfofIcsP2a5bIsM2a986lfyzLXw7m5aYbybIHICR39Ie4SnS+RYnKxs0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774392395; c=relaxed/simple; bh=3YDYe+eKvpUXHiyvLACVGcDJXT1eIj28IFAVn7VoE+4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=K8bGT8WHBeNgOBU52P6j4jhEnijtNy865bibOe781vdEiMfXqnl8KsVMl8X0zkeECR+S/GPMzAdQJ9RnQ2+KQcggbWMjpW6vnZbABs5IEMYrg4/2Mtjr1a0P51koOZqhyLmxH0nDGjVoIN+uO/40p6NEiwZJheUrE3t3SJcAwnw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.com; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.167.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-lf1-f45.google.com with SMTP id 2adb3069b0e04-5a27eb8311bso4358309e87.1 for ; Tue, 24 Mar 2026 15:46:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774392392; x=1774997192; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=cwV/BjEvjB+2xLn3P/yF4TbYfG+FKFLU/kxsrZgmYEA=; b=W/7zfI1tuHmkgIvQaopFR/slOSZL5p4376WvSOIj/4t+6R9+UK3WOrWZrVfoFEI+/x /YoV0iT3d4h+RayWc9guNnjXLfHp0W84zRgtypdwKxIK+fj3TwDQVNmnonY5mIjVvOC6 L1iBOnZRYlrfHO+VdveJ149Ffw9yKkaYYgxuP78irmjpb2XzDnQniCHK6eF43EUOQdjp +RXjQCBCluTKTKYRKF6HJG4BNNB93ZxQ4WFXP6AsL2L7w2QyTyqYKRJMQh0ltOEvN57q at72Xl1gFhHuhg9kGpEUwk0a00c79pbnmVZHhzYuLF5+gDzQ6GvcUeB7VdR2bQvbb039 F1Sg== X-Forwarded-Encrypted: i=1; AJvYcCUd81FEgOrAvGEZWF+NUjfRMIAM7C8MVvuIZhto2MZ/sBMie/DVlL/ZxJ5bNd4cSIP51HZRUgyLK1xkgM4=@vger.kernel.org X-Gm-Message-State: AOJu0YzujjwktNBcsXxhB/ul1nae7fkzTMmkB2kTjKQkObXA5vIl/FSH 6cYbti2/kWQA6wxJXWWHxRFVH7vkNtTgcYPjwbmTFQralsW5vUZ7Ixt9 X-Gm-Gg: ATEYQzx/X3zXGmjbXDvIUMQIQaXriMEvzemcQ2I07dJ+exMfthKOOTyNMCwHQhttk7x GX/pQBDWYQW0QitIzdfukcs8rudC4nVXOtAkwvurrEJvwR8GRx8Jo/eofgp7Urp9swdMx6ecNZt QxSZg60vgvUcRHhBKkFCknPthtRxz2kywF+deETMkowWYFx8pWuur7Ojx5oJDZPHCHCdUoFbEQ/ NtVnQg92HPVeFfpxIhK5CORqyAMMEBE00bndrT34VKt3uchhLX5smPJgm25VZiT0TNHUrVjc6KV zFMFBelL5PTae7iayzp9iAiFL8G74vdu5atI04Wr9WJPCRGI9YcQD3nd0aQt152uErIZYruthmz NoS5Abdan0zJHY1CZjycyw2b90QI1dt2V4HCOpu75aFFIjsIUfRlK+kfb8ortoYt1beU0X6eAHc xgZM0xQu//e14BicWyIS+N X-Received: by 2002:a05:6512:1250:b0:5a2:86bf:28cf with SMTP id 2adb3069b0e04-5a29b990918mr350145e87.29.1774392392094; Tue, 24 Mar 2026 15:46:32 -0700 (PDT) Received: from hackbase ([213.87.129.220]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-5a298fe3383sm626971e87.9.2026.03.24.15.46.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Mar 2026 15:46:30 -0700 (PDT) From: Alexander Popov To: Andrew Lunn , Jakub Kicinski , David Miller , Eric Dumazet , Paolo Abeni , Simon Horman , Maxime Chevallier , Michal Kubecek , Gal Pressman , Kory Maincent , Oleksij Rempel , Ido Schimmel , Heiner Kallweit , Greg KH , Johannes Berg , James Guan , Kees Cook , Paul Moses , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Popov Cc: security@kernel.org, notify@kernel.org Subject: [PATCH] wifi: virt_wifi: remove SET_NETDEV_DEV to avoid use-after-free Date: Wed, 25 Mar 2026 01:46:02 +0300 Message-ID: <20260324224607.374327-1-alex.popov@linux.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 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_op= s_begin") Cc: stable@vger.kernel.org Signed-off-by: Alexander Popov Acked-by: Greg Kroah-Hartman Reviewed-by: Breno Leitao --- drivers/net/wireless/virtual/virt_wifi.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/wireless/virtual/virt_wifi.c b/drivers/net/wireles= s/virtual/virt_wifi.c index 885dc7243e8d..97bd39d89e98 100644 --- a/drivers/net/wireless/virtual/virt_wifi.c +++ b/drivers/net/wireless/virtual/virt_wifi.c @@ -557,7 +557,6 @@ static int virt_wifi_newlink(struct net_device *dev, eth_hw_addr_inherit(dev, priv->lowerdev); netif_stacked_transfer_operstate(priv->lowerdev, dev); =20 - SET_NETDEV_DEV(dev, &priv->lowerdev->dev); dev->ieee80211_ptr =3D kzalloc_obj(*dev->ieee80211_ptr); =20 if (!dev->ieee80211_ptr) { --=20 2.53.0