CVE-2023-54149
- Source
- https://cve.org/CVERecord?id=CVE-2023-54149
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54149.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2023-54149
- Downstream
- Related
- Published
- 2025-12-24T13:07:00Z
- Modified
- 2026-08-12T03:51:28Z
- Severity
-
- 7.5 (High) CVSS_V3 - CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addresses
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addresses
When using the felix driver (the only one which supports UC filtering and MC filtering) as a DSA master for a random other DSA switch, one can see the following stack trace when the downstream switch ports join a VLAN-aware bridge:
============================= WARNING: suspicious RCU usage
net/8021q/vlan_core.c:238 suspicious rcu_dereference_protected() usage!
stack backtrace: Workqueue: dsa_ordered dsa_slave_switchdev_event_work Call trace: lockdep_rcu_suspicious+0x170/0x210 vlan_for_each+0x8c/0x188 dsa_slave_sync_uc+0x128/0x178 __hw_addr_sync_dev+0x138/0x158 dsa_slave_set_rx_mode+0x58/0x70 __dev_set_rx_mode+0x88/0xa8 dev_uc_add+0x74/0xa0 dsa_port_bridge_host_fdb_add+0xec/0x180 dsa_slave_switchdev_event_work+0x7c/0x1c8 process_one_work+0x290/0x568
What it's saying is that vlan_for_each() expects rtnl_lock() context and it's not getting it, when it's called from the DSA master's ndo_set_rx_mode().
The caller of that - dsa_slave_set_rx_mode() - is the slave DSA interface's dsa_port_bridge_host_fdb_add() which comes from the deferred dsa_slave_switchdev_event_work().
We went to great lengths to avoid the rtnl_lock() context in that call path in commit 0faf890fc519 ("net: dsa: drop rtnl_lock from dsa_slave_switchdev_event_work"), and calling rtnl_lock() is simply not an option due to the possibility of deadlocking when calling dsa_flush_workqueue() from the call paths that do hold rtnl_lock() - basically all of them.
So, when the DSA master calls vlan_for_each() from its ndo_set_rx_mode(), the state of the 8021q driver on this device is really not protected from concurrent access by anything.
Looking at net/8021q/, I don't think that vlan_info->vid_list was particularly designed with RCU traversal in mind, so introducing an RCU read-side form of vlan_for_each() - vlan_for_each_rcu() - won't be so easy, and it also wouldn't be exactly what we need anyway.
In general I believe that the solution isn't in net/8021q/ anyway; vlan_for_each() is not cut out for this task. DSA doesn't need rtnl_lock() to be held per se - since it's not a netdev state change that we're blocking, but rather, just concurrent additions/removals to a VLAN list. We don't even need sleepable context - the callback of vlan_for_each() just schedules deferred work.
The proposed escape is to remove the dependency on vlan_for_each() and to open-code a non-sleepable, rtnl-free alternative to that, based on copies of the VLAN list modified from .ndo_vlan_rx_add_vid() and .ndo_vlan_rx_kill_vid().
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54149.json" }- References
-
- https://git.kernel.org/stable/c/3948c69b3837fec2ee5a90fbc911c343199be0ac
- https://git.kernel.org/stable/c/3f9e79f31e51b7d5bf95c617540deb6cf2816a3f
- https://git.kernel.org/stable/c/d06f925f13976ab82167c93467c70a337a0a3cda
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54149.json
- https://nvd.nist.gov/vuln/detail/CVE-2023-54149
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced64fdc5f341db01200e33105265d4b8450122a82eFixed3948c69b3837fec2ee5a90fbc911c343199be0acFixed3f9e79f31e51b7d5bf95c617540deb6cf2816a3fFixedd06f925f13976ab82167c93467c70a337a0a3cda
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedLast Affected2daf967a24334865e51520e55190a646dd480cd7
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6.2.10Fixed6.3