CVE-2023-53105 net/mlx5e: Fix cleanup null-ptr deref on encap lock
A null pointer dereference in the Linux kernel's mlx5e driver can cause a system crash during module unloading with active offloaded traffic.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53105?
CVE-2023-53105 is a medium-severity vulnerability in Linux kernel, published on 2 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix cleanup null-ptr deref on encap lock
During module is unloaded while a peer tc flow is still offloaded, first the peer uplink rep profile is changed to a nic profile, and so neigh encap lock is destroyed. Next during unload, the VF reps netdevs are unregistered which causes the original non-peer tc flow to be deleted, which deletes the peer flow. The peer flow deletion detaches the encap entry and try to take the already destroyed encap lock, causing the below trace.
Fix this by clearing peer flows during tc eswitch cleanup (mlx5e_tc_esw_cleanup()).
Relevant trace: [ 4316.837128] BUG: kernel NULL pointer dereference, address: 00000000000001d8 [ 4316.842239] RIP: 0010:__mutex_lock+0xb5/0xc40 [ 4316.851897] Call Trace: [ 4316.852481] <TASK> [ 4316.857214] mlx5e_rep_neigh_entry_release+0x93/0x790 [mlx5_core] [ 4316.858258] mlx5e_rep_encap_entry_detach+0xa7/0xf0 [mlx5_core] [ 4316.859134] mlx5e_encap_dealloc+0xa3/0xf0 [mlx5_core] [ 4316.859867] clean_encap_dests.part.0+0x5c/0xe0 [mlx5_core] [ 4316.860605] mlx5e_tc_del_fdb_flow+0x32a/0x810 [mlx5_core] [ 4316.862609] __mlx5e_tc_del_fdb_peer_flow+0x1a2/0x250 [mlx5_core] [ 4316.863394] mlx5e_tc_del_flow+0x(/0x630 [mlx5_core] [ 4316.864090] mlx5e_flow_put+0x5f/0x100 [mlx5_core] [ 4316.864771] mlx5e_delete_flower+0x4de/0xa40 [mlx5_core] [ 4316.865486] tc_setup_cb_reoffload+0x20/0x80 [ 4316.865905] fl_reoffload+0x47c/0x510 [cls_flower] [ 4316.869181] tcf_block_playback_offloads+0x91/0x1d0 [ 4316.869649] tcf_block_unbind+0xe7/0x1b0 [ 4316.870049] tcf_block_offload_cmd.isra.0+0x1ee/0x270 [ 4316.879266] tcf_block_offload_unbind+0x61/0xa0 [ 4316.879711] __tcf_block_put+0xa4/0x310
Weakness: CWE-476
Which versions are affected by CVE-2023-53105?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-53105?
Apply the vendor's patch.
Is CVE-2023-53105 being exploited?
There is no known exploitation of CVE-2023-53105 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-69923, BELL-CVE-2023-53105, DEBIAN-CVE-2023-53105, GHSA-w3vx-37cc-jxmm, ROOT-OS-DEBIAN-11-CVE-2023-53105, ROOT-OS-UBUNTU-2204-CVE-2023-53105 and 1 more.