virtio_net: fix device mismatch in devm_kzalloc/devm_kfree
CVE: CVE-2026-23046
Component: kernel
CWE: CWE-672
Severity: Moderate
CVSS v3: 5.6/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Release date: 2026-02-04T00:00:00+00:00

In the Linux kernel, the following vulnerability has been resolved:

virtio_net: fix device mismatch in devm_kzalloc/devm_kfree

Initial rss_hdr allocation uses virtio_device->device,
but virtnet_set_queues() frees using net_device->device.
This device mismatch causing below devres warning

[ 3788.514041] ------------[ cut here ]------------
[ 3788.514044] WARNING: drivers/base/devres.c:1095 at devm_kfree+0x84/0x98, CPU#16: vdpa/1463
[ 3788.514054] Modules linked in: octep_vdpa virtio_net virtio_vdpa [last unloaded: virtio_vdpa]
[ 3788.514064] CPU: 16 UID: 0 PID: 1463 Comm: vdpa Tainted: G        W           6.18.0 #10 PREEMPT
[ 3788.514067] Tainted: [W]=WARN
[ 3788.514069] Hardware name: Marvell CN106XX board (DT)
[ 3788.514071] pstate: 63400009 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
[ 3788.514074] pc : devm_kfree+0x84/0x98
[ 3788.514076] lr : devm_kfree+0x54/0x98
[ 3788.514079] sp : ffff800084e2f220
[ 3788.514080] x29: ffff800084e2f220 x28: ffff0003b2366000 x27: 000000000000003f
[ 3788.514085] x26: 000000000000003f x25: ffff000106f17c10 x24: 0000000000000080
[ 3788.514089] x23: ffff00045bb8ab08 x22: ffff00045bb8a000 x21: 0000000000000018
[ 3788.514093] x20: ffff0004355c3080 x19: ffff00045bb8aa00 x18: 0000000000080000
[ 3788.514098] x17: 0000000000000040 x16: 000000000000001f x15: 000000000007ffff
[ 3788.514102] x14: 0000000000000488 x13: 0000000000000005 x12: 00000000000fffff
[ 3788.514106] x11: ffffffffffffffff x10: 0000000000000005 x9 : ffff800080c8c05c
[ 3788.514110] x8 : ffff800084e2eeb8 x7 : 0000000000000000 x6 : 000000000000003f
[ 3788.514115] x5 : ffff8000831bafe0 x4 : ffff800080c8b010 x3 : ffff0004355c3080
[ 3788.514119] x2 : ffff0004355c3080 x1 : 0000000000000000 x0 : 0000000000000000
[ 3788.514123] Call trace:
[ 3788.514125]  devm_kfree+0x84/0x98 (P)
[ 3788.514129]  virtnet_set_queues+0x134/0x2e8 [virtio_net]
[ 3788.514135]  virtnet_probe+0x9c0/0xe00 [virtio_net]
[ 3788.514139]  virtio_dev_probe+0x1e0/0x338
[ 3788.514144]  really_probe+0xc8/0x3a0
[ 3788.514149]  __driver_probe_device+0x84/0x170
[ 3788.514152]  driver_probe_device+0x44/0x120
[ 3788.514155]  __device_attach_driver+0xc4/0x168
[ 3788.514158]  bus_for_each_drv+0x8c/0xf0
[ 3788.514161]  __device_attach+0xa4/0x1c0
[ 3788.514164]  device_initial_probe+0x1c/0x30
[ 3788.514168]  bus_probe_device+0xb4/0xc0
[ 3788.514170]  device_add+0x614/0x828
[ 3788.514173]  register_virtio_device+0x214/0x258
[ 3788.514175]  virtio_vdpa_probe+0xa0/0x110 [virtio_vdpa]
[ 3788.514179]  vdpa_dev_probe+0xa8/0xd8
[ 3788.514183]  really_probe+0xc8/0x3a0
[ 3788.514186]  __driver_probe_device+0x84/0x170
[ 3788.514189]  driver_probe_device+0x44/0x120
[ 3788.514192]  __device_attach_driver+0xc4/0x168
[ 3788.514195]  bus_for_each_drv+0x8c/0xf0
[ 3788.514197]  __device_attach+0xa4/0x1c0
[ 3788.514200]  device_initial_probe+0x1c/0x30
[ 3788.514203]  bus_probe_device+0xb4/0xc0
[ 3788.514206]  device_add+0x614/0x828
[ 3788.514209]  _vdpa_register_device+0x58/0x88
[ 3788.514211]  octep_vdpa_dev_add+0x104/0x228 [octep_vdpa]
[ 3788.514215]  vdpa_nl_cmd_dev_add_set_doit+0x2d0/0x3c0
[ 3788.514218]  genl_family_rcv_msg_doit+0xe4/0x158
[ 3788.514222]  genl_rcv_msg+0x218/0x298
[ 3788.514225]  netlink_rcv_skb+0x64/0x138
[ 3788.514229]  genl_rcv+0x40/0x60
[ 3788.514233]  netlink_unicast+0x32c/0x3b0
[ 3788.514237]  netlink_sendmsg+0x170/0x3b8
[ 3788.514241]  __sys_sendto+0x12c/0x1c0
[ 3788.514246]  __arm64_sys_sendto+0x30/0x48
[ 3788.514249]  invoke_syscall.constprop.0+0x58/0xf8
[ 3788.514255]  do_el0_svc+0x48/0xd0
[ 3788.514259]  el0_svc+0x48/0x210
[ 3788.514264]  el0t_64_sync_handler+0xa0/0xe8
[ 3788.514268]  el0t_64_sync+0x198/0x1a0
[ 3788.514271] ---[ end trace 0000000000000000 ]---

Fix by using virtio_device->device consistently for
allocation and deallocation

Statement: virtio_net allocated rss_hdr with devm_kzalloc using one struct device but later freed the same pointer with devm_kfree using a different struct device. This devres ownership mismatch triggers warnings in devm_kfree and can lead to incorrect resource lifetime handling during queue and RSS reconfiguration error paths. For the CVSS the PR value in the paranoid score is PR:L because triggering virtnet_set_queues and related vdpa or netlink configuration paths may be possible for users with limited network administration capabilities in some deployments. The issue is not network reachable in the sense of remote packet input. Impact is primarily denial of service through warning storms and potential resource leaks during repeated configuration or probe failure scenarios.

Remediation: