CVE-2026-74421: drm/rockchip: dw_dp: Switch to drmm_kzalloc()
In the Linux kernel, the following vulnerability has been resolved:
drm/rockchip: dwdp: Switch to drmmkzalloc()
Driver makes use of drmmencoderinit() to initialize the encoder and automatically handle the cleanup by registering drmencodercleanup() with drmmaddaction().
However, the internal structure containing the encoder part gets allocated with devmkzalloc(), which happens while componentbindall() is being called from Rockchip DRM driver. The component framework further ensures it is deallocated as part of releasing all the resources claimed during bind, which is triggered from componentunbindall().
When the reference to the DRM device gets eventually dropped via drmdevput() in rockchipdrmunbind(), drmmencoderallocrelease() attempts to access the now released encoder structure, leading to use-after-free.
Ensure driver's internal structure is still reachable on encoder cleanup by switching from a device-managed allocation to a drm-managed one.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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ubuntu/linux-aws-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
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ubuntu/linux-azure-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17~24.04.1 - Upgrade
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ubuntu/linux-azure-fde-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1016.16~24.04.1 - Upgrade
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ubuntu/linux-gcp-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
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ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38~24.04.4 - Upgrade
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ubuntu/linux-nvidia-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1024.25~24.04.1 - Upgrade
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ubuntu/linux-oracle-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1013.13~24.04.1 - Upgrade
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ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1~24.04.1 - Upgrade
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ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-38.38 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
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ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 7.0.0-1016.16 - Upgrade
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ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
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ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 7.0.0-1008.9 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
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ubuntu/linux-nvidia-bosto a version that resolves this vulnerability.Fixed in 7.0.0-2022.23 - Upgrade
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ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1013.13 - Upgrade
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ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Upgrade
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ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Compensating control
In the Rockchip DRM dw_dp driver, replace the device-managed devm_kzalloc() allocation for the internal structure containing the encoder with the DRM-managed drmm_kzalloc() allocation, so it remains reachable during encoder cleanup.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-74421?
CVE-2026-74421 has a risk score of 40.
What type of vulnerability is CVE-2026-74421?
CVE-2026-74421 is classified as a Use After Free vulnerability.
How do I fix CVE-2026-74421?
Fixing CVE-2026-74421 involves updating the Linux kernel to a version where this vulnerability has been addressed.
What component is affected by CVE-2026-74421?
CVE-2026-74421 affects the drm/rockchip: dw_dp component of the Linux kernel.
When was CVE-2026-74421 published?
CVE-2026-74421 was published on August 15, 2026.