GHSA-2fmc-xx62-q6fmunknown

In the Linux kernel, the following vulnerability has been resolved: coresight: etm4x: fix...

Published
September 17, 2026
Last Modified
September 17, 2026

🔗 CVE IDs covered (1)

📋 Description

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 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 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 relevant fields setup.

🔗 References (9)