CVE Catalog

CVE-2026-90274

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel, the coresight etm4x driver's use of (nrseqstate - 1) in the loop initializing or setting TRCSEQEVR<n> can cause an underflow when TRCIDR5.NUMSEQSTATE is 0b000. The fix introduces an nr_seq_ctrls field and an ETM_MAX_SEQ_TRANSITIONS macro and applies them to TRCSEQEVR<n> field setup.

Risk Assessment

The underflow can lead to invalid memory access or a kernel crash when using CoreSight ETM tracing. It affects debugging reliability and system stability on platforms with ETM4x.

Recommendation

Update the Linux kernel to a version containing the fix that introduces nr_seq_ctrls and the ETM_MAX_SEQ_TRANSITIONS macro. The update mainly affects platforms using CoreSight ETM4x.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: coresight: etm4x: fix underflow for usage of (nrseqstate - 1) According to IHI006H Embedded Trace Macrocell Architecture Specification[0], TRCSEQEVR<n> is implemented only when TRCIDR5.NUMSEQSTATE is 0b100, in which case n ranges from 0 to 2; otherwise, TRCIDR5.NUMSEQSTATE is 0b000. IOW, the number of usage in the initialisation or setting TRCSEQEVR<n> with drvdata->nrseqstate - 1 in the loop could make underflow issue when TRCIDR5.NUMSEQSTATE is 0b000. Therefore, introduce nr_seq_ctrls field and untie it from nrseqstate. As part of this introduce ETM_MAX_SEQ_TRANSITIONS macro and apply nr_seq_ctrls and above macro to TRCSEQEVR<n> relevant fields setup.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS