CVE-2022-49427 iommu/mediatek: Remove clk_disable in mtk_iommu_remove
A kernel warning triggered by redundant clock disabling during device removal can lead to system instability or denial of service.
- 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-2022-49427?
CVE-2022-49427 is a medium-severity denial of service 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:
iommu/mediatek: Remove clk_disable in mtk_iommu_remove
After the commit b34ea31fe013 ("iommu/mediatek: Always enable the clk on resume"), the iommu clock is controlled by the runtime callback. thus remove the clk control in the mtk_iommu_remove.
Otherwise, it will warning like:
echo 14018000.iommu > /sys/bus/platform/drivers/mtk-iommu/unbind
[ 51.413044] ------------[ cut here ]------------ [ 51.413648] vpp0_smi_iommu already disabled [ 51.414233] WARNING: CPU: 2 PID: 157 at */v5.15-rc1/kernel/mediatek/ drivers/clk/clk.c:952 clk_core_disable+0xb0/0xb8 [ 51.417174] Hardware name: MT8195V/C(ENG) (DT) [ 51.418635] pc : clk_core_disable+0xb0/0xb8 [ 51.419177] lr : clk_core_disable+0xb0/0xb8 ... [ 51.429375] Call trace: [ 51.429694] clk_core_disable+0xb0/0xb8 [ 51.430193] clk_core_disable_lock+0x24/0x40 [ 51.430745] clk_disable+0x20/0x30 [ 51.431189] mtk_iommu_remove+0x58/0x118 [ 51.431705] platform_remove+0x28/0x60 [ 51.432197] device_release_driver_internal+0x110/0x1f0 [ 51.432873] device_driver_detach+0x18/0x28 [ 51.433418] unbind_store+0xd4/0x108 [ 51.433886] drv_attr_store+0x24/0x38 [ 51.434363] sysfs_kf_write+0x40/0x58 [ 51.434843] kernfs_fop_write_iter+0x164/0x1e0
Which versions are affected by CVE-2022-49427?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49427?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-49427 being exploited?
There is no known exploitation of CVE-2022-49427 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49427, GHSA-q88h-gvfq-84pc, UBUNTU-CVE-2022-49427.