UBUNTU-CVE-2026-68276: Buffer Overflow
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/gfx: fix cleaner shader IB buffer overflow The cleaner shader sysfs path allocates a 16-dword (64 byte) IB but incorrectly fills (alignmask + 1) dwords. On GFX rings alignmask is 0xff, so the loop wrote 256 dwords into a 64-byte buffer, causing a kernel page fault. The IB only needs to be a minimal NOP shell to schedule the job; the cleaner shader itself is emitted on the ring via emitcleanershader(). Fill 16 dwords to match the allocation. v2: Use ibsizedw variable (Lijo) (cherry picked from commit bf21af331ebf72d0935fd70c73192414a422c03a)
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
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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 - Upgrade
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Patch bf21af331ebf72d0935fd70c73192414a422c03a
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using the listed Ubuntu kernel packages are affected only where the AMDGPU cleaner shader sysfs path can be exercised on GFX rings. The provided data does not identify other drivers or hardware families as affected.
What triggers the overflow?
The overflow occurs when the cleaner shader sysfs path creates an instruction buffer. It allocates 16 dwords (64 bytes) but, on GFX rings with an align_mask of 0xff, writes 256 dwords, which can cause a kernel page fault.
What is the practical impact of triggering it?
The described result is a kernel page fault caused by writing beyond the allocated instruction buffer. The supplied information does not establish code execution, privilege escalation, or data disclosure.
How can I tell whether a system has encountered this issue?
A kernel page fault associated with the AMDGPU cleaner shader sysfs path is the stated symptom. The provided data does not include a specific log signature, affected package version, or detection command.