iommu/mediatek: Always enable the clk on resume
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: iommu/mediatek: Always enable the clk on resume In mtk_iommu_runtime_resume always enable the clk, even if m4u_dom is null. Otherwise the 'suspend' cb might disable the clk which is already disabled causing the warning: [ 1.586104] infra_m4u already disabled [ 1.586133] WARNING: CPU: 0 PID: 121 at drivers/clk/clk.c:952 clk_core_disable+0xb0/0xb8 [ 1.594391] mtk-iommu 10205000.iommu: bound 18001000.larb (ops mtk_smi_larb_component_ops) [ 1.598108] Modules linked in: [ 1.598114] CPU: 0 PID: 121 Comm: kworker/0:2 Not tainted 5.12.0-rc5 #69 [ 1.609246] mtk-iommu 10205000.iommu: bound 14027000.larb (ops mtk_smi_larb_component_ops) [ 1.617487] Hardware name: Google Elm (DT) [ 1.617491] Workqueue: pm pm_runtime_work [ 1.620545] mtk-iommu 10205000.iommu: bound 19001000.larb (ops mtk_smi_larb_component_ops) [ 1.627229] pstate: 60000085 (nZCv daIf -PAN -UAO -TCO BTYPE=--) [ 1.659297] pc : clk_core_disable+0xb0/0xb8 [ 1.663475] lr : clk_core_disable+0xb0/0xb8 [ 1.667652] sp : ffff800011b9bbe0 [ 1.670959] x29: ffff800011b9bbe0 x28: 0000000000000000 [ 1.676267] x27: ffff800011448000 x26: ffff8000100cfd98 [ 1.681574] x25: ffff800011b9bd48 x24: 0000000000000000 [ 1.686882] x23: 0000000000000000 x22: ffff8000106fad90 [ 1.692189] x21: 000000000000000a x20: ffff0000c0048500 [ 1.697496] x19: ffff0000c0048500 x18: ffffffffffffffff [ 1.702804] x17: 0000000000000000 x16: 0000000000000000 [ 1.708112] x15: ffff800011460300 x14: fffffffffffe0000 [ 1.713420] x13: ffff8000114602d8 x12: 0720072007200720 [ 1.718727] x11: 0720072007200720 x10: 0720072007200720 [ 1.724035] x9 : ffff800011b9bbe0 x8 : ffff800011b9bbe0 [ 1.729342] x7 : 0000000000000009 x6 : ffff8000114b8328 [ 1.734649] x5 : 0000000000000000 x4 : 0000000000000000 [ 1.739956] x3 : 00000000ffffffff x2 : ffff800011460298 [ 1.745263] x1 : 1af1d7de276f4500 x0 : 0000000000000000 [ 1.750572] Call trace: [ 1.753010] clk_core_disable+0xb0/0xb8 [ 1.756840] clk_core_disable_lock+0x24/0x40 [ 1.761105] clk_disable+0x20/0x30 [ 1.764501] mtk_iommu_runtime_suspend+0x88/0xa8 [ 1.769114] pm_generic_runtime_suspend+0x2c/0x48 [ 1.773815] __rpm_callback+0xe0/0x178 [ 1.777559] rpm_callback+0x24/0x88 [ 1.781041] rpm_suspend+0xdc/0x470 [ 1.784523] rpm_idle+0x12c/0x170 [ 1.787831] pm_runtime_work+0xa8/0xc0 [ 1.791573] process_one_work+0x1e8/0x360 [ 1.795580] worker_thread+0x44/0x478 [ 1.799237] kthread+0x150/0x158 [ 1.802460] ret_from_fork+0x10/0x30 [ 1.806034] ---[ end trace 82402920ef64573b ]--- [ 1.810728] ------------[ cut here ]------------ In addition, we now don't need to enable the clock from the function mtk_iommu_hw_init since it is already enabled by the resume.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.12.4, 5.13
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
Not affected: 2 products
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-47025
- 2026-10-03 Alias added: GHSA-w7xf-wp34-j8rv
References
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2021-47025 · CVE Program
- CVE-2021-47025 · NVD
- FIRST EPSS
- GHSA-w7xf-wp34-j8rv · GitHub Advisory Database · CC BY 4.0
- CVE-2021-47025 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences