# CVE-2022-49338: net/mlx5e: CT: Fix cleanup of CT before cleanup of TC ct rules

> Incorrect cleanup order in the Mellanox mlx5e driver causes a use-after-free condition, potentially leading to system crashes or denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** Yes
- **Published:** 26 Feb 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49338, GHSA-h32p-fx4x-w3v5, UBUNTU-CVE-2022-49338

## What is CVE-2022-49338?

CVE-2022-49338 is a medium-severity use after free vulnerability in Linux kernel, published on 26 Feb 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: CT: Fix cleanup of CT before cleanup of TC ct rules

CT cleanup assumes that all tc rules were deleted first, and so
is free to delete the CT shared resources (e.g the dr_action
fwd_action which is shared for all tuples). But currently for
uplink, this is happens in reverse, causing the below trace.

CT cleanup is called from:
mlx5e_cleanup_rep_tx()->mlx5e_cleanup_uplink_rep_tx()->
mlx5e_rep_tc_cleanup()->mlx5e_tc_esw_cleanup()->
mlx5_tc_ct_clean()

Only afterwards, tc cleanup is called from:
mlx5e_cleanup_rep_tx()->mlx5e_tc_ht_cleanup()
which would have deleted all the tc ct rules, and so delete
all the offloaded tuples.

Fix this reversing the order of init and on cleanup, which
will result in tc cleanup then ct cleanup.

[ 9443.593347] WARNING: CPU: 2 PID: 206774 at drivers/net/ethernet/mellanox/mlx5/core/steering/dr_action.c:1882 mlx5dr_action_destroy+0x188/0x1a0 [mlx5_core]
[ 9443.593349] Modules linked in: act_ct nf_flow_table rdma_ucm(O) rdma_cm(O) iw_cm(O) ib_ipoib(O) ib_cm(O) ib_umad(O) mlx5_core(O-) mlxfw(O) mlxdevm(O) auxiliary(O) ib_uverbs(O) psample ib_core(O) mlx_compat(O) ip_gre gre ip_tunnel act_vlan bonding geneve esp6_offload esp6 esp4_offload esp4 act_tunnel_key vxlan ip6_udp_tunnel udp_tunnel act_mirred act_skbedit act_gact cls_flower sch_ingress nfnetlink_cttimeout nfnetlink xfrm_user xfrm_algo 8021q garp stp ipmi_devintf mrp ipmi_msghandler llc openvswitch nsh nf_conncount nf_nat mst_pciconf(O) dm_multipath sbsa_gwdt uio_pdrv_genirq uio mlxbf_pmc mlxbf_pka mlx_trio mlx_bootctl(O) bluefield_edac sch_fq_codel ip_tables ipv6 crc_ccitt btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor xor_neon raid6_pq raid1 raid0 crct10dif_ce i2c_mlxbf gpio_mlxbf2 mlxbf_gige aes_neon_bs aes_neon_blk [last unloaded: mlx5_ib]
[ 9443.593419] CPU: 2 PID: 206774 Comm: modprobe Tainted: G           O      5.4.0-1023.24.gc14613d-bluefield #1
[ 9443.593422] Hardware name: https://www.mellanox.com BlueField SoC/BlueField SoC, BIOS BlueField:143ebaf Jan 11 2022
[ 9443.593424] pstate: 20000005 (nzCv daif -PAN -UAO)
[ 9443.593489] pc : mlx5dr_action_destroy+0x188/0x1a0 [mlx5_core]
[ 9443.593545] lr : mlx5_ct_fs_smfs_destroy+0x24/0x30 [mlx5_core]
[ 9443.593546] sp : ffff8000135dbab0
[ 9443.593548] x29: ffff8000135dbab0 x28: ffff0003a6ab8e80
[ 9443.593550] x27: 0000000000000000 x26: ffff0003e07d7000
[ 9443.593552] x25: ffff800009609de0 x24: ffff000397fb2120
[ 9443.593554] x23: ffff0003975c0000 x22: 0000000000000000
[ 9443.593556] x21: ffff0003975f08c0 x20: ffff800009609de0
[ 9443.593558] x19: ffff0003c8a13380 x18: 0000000000000014
[ 9443.593560] x17: 0000000067f5f125 x16: 000000006529c620
[ 9443.593561] x15: 000000000000000b x14: 0000000000000000
[ 9443.593563] x13: 0000000000000002 x12: 0000000000000001
[ 9443.593565] x11: ffff800011108868 x10: 0000000000000000
[ 9443.593567] x9 : 0000000000000000 x8 : ffff8000117fb270
[ 9443.593569] x7 : ffff0003ebc01288 x6 : 0000000000000000
[ 9443.593571] x5 : ffff800009591ab8 x4 : fffffe000f6d9a20
[ 9443.593572] x3 : 0000000080040001 x2 : fffffe000f6d9a20
[ 9443.593574] x1 : ffff8000095901d8 x0 : 0000000000000025
[ 9443.593577] Call trace:
[ 9443.593634]  mlx5dr_action_destroy+0x188/0x1a0 [mlx5_core]
[ 9443.593688]  mlx5_ct_fs_smfs_destroy+0x24/0x30 [mlx5_core]
[ 9443.593743]  mlx5_tc_ct_clean+0x34/0xa8 [mlx5_core]
[ 9443.593797]  mlx5e_tc_esw_cleanup+0x58/0x88 [mlx5_core]
[ 9443.593851]  mlx5e_rep_tc_cleanup+0x24/0x30 [mlx5_core]
[ 9443.593905]  mlx5e_cleanup_rep_tx+0x6c/0x78 [mlx5_core]
[ 9443.593959]  mlx5e_detach_netdev+0x74/0x98 [mlx5_core]
[ 9443.594013]  mlx5e_netdev_change_profile+0x70/0x180 [mlx5_core]
[ 9443.594067]  mlx5e_netdev_attach_nic_profile+0x34/0x40 [mlx5_core]
[ 9443.594122]  mlx5e_vport_rep_unload+0x15c/0x1a8 [mlx5_core]
[ 9443.594177]  mlx5_eswitch_unregister_vport_reps+0x228/0x298 [mlx5_core]
[ 9443.594231]  mlx5e_rep_remove+0x2c/0x38
---truncated---

## Which versions are affected by CVE-2022-49338?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49338?

Apply the vendor's patch.

## Is CVE-2022-49338 being exploited?

There is no known exploitation of CVE-2022-49338 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-49338 and fix it if it is affected.

What it is: CVE-2022-49338 is a medium-severity use after free vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-49338 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-49338/ (Markdown: https://insights.sbomify.com/CVE-2022-49338/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49338
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49338
- OSV: https://osv.dev/vulnerability/CVE-2022-49338

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49338/
Summaries are generated and may contain mistakes; the official description above is the record.
