CVE-2026-97515

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

i3c: master: svc: Prevent IRQ storm from false SLVSTART on NPCM845

On NPCM845, when a target on the I3C bus gets stuck holding SDA low,

the controller reports a false Master Request (MR) in-band interrupt

event. The driver handles this by emitting a STOP condition to restore

the bus.

However, the hardware quirk SVC_I3C_QUIRK_FALSE_SLVSTART indicates that

emitting a STOP condition may spuriously set the SLVSTART interrupt

status bit. In the Master Request case, this creates a feedback loop:

the STOP triggers a new SLVSTART event, the IRQ handler fires again,

the controller still reports an MR type, another STOP is emitted, and

the cycle repeats indefinitely, resulting in an IRQ storm that can lock

up the CPU.

Clear the SLVSTART status bit explicitly after emitting the STOP in the

Master Request IBI handler when the SVC_I3C_QUIRK_FALSE_SLVSTART quirk

is set. This breaks the feedback loop without affecting normal SLVS

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References