lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Message-ID: <2025050132-CVE-2025-23163-dd12@gregkh>
Date: Thu,  1 May 2025 14:56:43 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2025-23163: net: vlan: don't propagate flags on open

From: Greg Kroah-Hartman <gregkh@...nel.org>

Description
===========

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

net: vlan: don't propagate flags on open

With the device instance lock, there is now a possibility of a deadlock:

[    1.211455] ============================================
[    1.211571] WARNING: possible recursive locking detected
[    1.211687] 6.14.0-rc5-01215-g032756b4ca7a-dirty #5 Not tainted
[    1.211823] --------------------------------------------
[    1.211936] ip/184 is trying to acquire lock:
[    1.212032] ffff8881024a4c30 (&dev->lock){+.+.}-{4:4}, at: dev_set_allmulti+0x4e/0xb0
[    1.212207]
[    1.212207] but task is already holding lock:
[    1.212332] ffff8881024a4c30 (&dev->lock){+.+.}-{4:4}, at: dev_open+0x50/0xb0
[    1.212487]
[    1.212487] other info that might help us debug this:
[    1.212626]  Possible unsafe locking scenario:
[    1.212626]
[    1.212751]        CPU0
[    1.212815]        ----
[    1.212871]   lock(&dev->lock);
[    1.212944]   lock(&dev->lock);
[    1.213016]
[    1.213016]  *** DEADLOCK ***
[    1.213016]
[    1.213143]  May be due to missing lock nesting notation
[    1.213143]
[    1.213294] 3 locks held by ip/184:
[    1.213371]  #0: ffffffff838b53e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock+0x1b/0xa0
[    1.213543]  #1: ffffffff84e5fc70 (&net->rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock+0x37/0xa0
[    1.213727]  #2: ffff8881024a4c30 (&dev->lock){+.+.}-{4:4}, at: dev_open+0x50/0xb0
[    1.213895]
[    1.213895] stack backtrace:
[    1.213991] CPU: 0 UID: 0 PID: 184 Comm: ip Not tainted 6.14.0-rc5-01215-g032756b4ca7a-dirty #5
[    1.213993] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
[    1.213994] Call Trace:
[    1.213995]  <TASK>
[    1.213996]  dump_stack_lvl+0x8e/0xd0
[    1.214000]  print_deadlock_bug+0x28b/0x2a0
[    1.214020]  lock_acquire+0xea/0x2a0
[    1.214027]  __mutex_lock+0xbf/0xd40
[    1.214038]  dev_set_allmulti+0x4e/0xb0 # real_dev->flags & IFF_ALLMULTI
[    1.214040]  vlan_dev_open+0xa5/0x170 # ndo_open on vlandev
[    1.214042]  __dev_open+0x145/0x270
[    1.214046]  __dev_change_flags+0xb0/0x1e0
[    1.214051]  netif_change_flags+0x22/0x60 # IFF_UP vlandev
[    1.214053]  dev_change_flags+0x61/0xb0 # for each device in group from dev->vlan_info
[    1.214055]  vlan_device_event+0x766/0x7c0 # on netdevsim0
[    1.214058]  notifier_call_chain+0x78/0x120
[    1.214062]  netif_open+0x6d/0x90
[    1.214064]  dev_open+0x5b/0xb0 # locks netdevsim0
[    1.214066]  bond_enslave+0x64c/0x1230
[    1.214075]  do_set_master+0x175/0x1e0 # on netdevsim0
[    1.214077]  do_setlink+0x516/0x13b0
[    1.214094]  rtnl_newlink+0xaba/0xb80
[    1.214132]  rtnetlink_rcv_msg+0x440/0x490
[    1.214144]  netlink_rcv_skb+0xeb/0x120
[    1.214150]  netlink_unicast+0x1f9/0x320
[    1.214153]  netlink_sendmsg+0x346/0x3f0
[    1.214157]  __sock_sendmsg+0x86/0xb0
[    1.214160]  ____sys_sendmsg+0x1c8/0x220
[    1.214164]  ___sys_sendmsg+0x28f/0x2d0
[    1.214179]  __x64_sys_sendmsg+0xef/0x140
[    1.214184]  do_syscall_64+0xec/0x1d0
[    1.214190]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[    1.214191] RIP: 0033:0x7f2d1b4a7e56

Device setup:

     netdevsim0 (down)
     ^        ^
  bond        netdevsim1.100@...devsim1 allmulticast=on (down)

When we enslave the lower device (netdevsim0) which has a vlan, we
propagate vlan's allmuti/promisc flags during ndo_open. This causes
(re)locking on of the real_dev.

Propagate allmulti/promisc on flags change, not on the open. There
is a slight semantics change that vlans that are down now propagate
the flags, but this seems unlikely to result in the real issues.

Reproducer:

  echo 0 1 > /sys/bus/netdevsim/new_device

  dev_path=$(ls -d /sys/bus/netdevsim/devices/netdevsim0/net/*)
  dev=$(echo $dev_path | rev | cut -d/ -f1 | rev)

  ip link set dev $dev name netdevsim0
  ip link set dev netdevsim0 up

  ip link add link netdevsim0 name netdevsim0.100 type vlan id 100
  ip link set dev netdevsim0.100 allmulticast on down
  ip link add name bond1 type bond mode 802.3ad
  ip link set dev netdevsim0 down
  ip link set dev netdevsim0 master bond1
  ip link set dev bond1 up
  ip link show

The Linux kernel CVE team has assigned CVE-2025-23163 to this issue.


Affected and fixed versions
===========================

	Fixed in 6.1.135 with commit 53fb25e90c0a503a17c639341ba5e755cb2feb5c
	Fixed in 6.6.88 with commit d537859e56bcc3091805c524484a4c85386b3cc8
	Fixed in 6.12.24 with commit 299d7d27af6b5844cda06a0fdfa635705e1bc50f
	Fixed in 6.13.12 with commit 8980018a9806743d9b80837330d46f06ecf78516
	Fixed in 6.14.3 with commit 538b43aa21e3b17c110104efd218b966d2eda5f8
	Fixed in 6.15-rc1 with commit 27b918007d96402aba10ed52a6af8015230f1793

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2025-23163
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	net/8021q/vlan_dev.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/53fb25e90c0a503a17c639341ba5e755cb2feb5c
	https://git.kernel.org/stable/c/d537859e56bcc3091805c524484a4c85386b3cc8
	https://git.kernel.org/stable/c/299d7d27af6b5844cda06a0fdfa635705e1bc50f
	https://git.kernel.org/stable/c/8980018a9806743d9b80837330d46f06ecf78516
	https://git.kernel.org/stable/c/538b43aa21e3b17c110104efd218b966d2eda5f8
	https://git.kernel.org/stable/c/27b918007d96402aba10ed52a6af8015230f1793

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ