CVE-2023-53583

/// Technical description

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

perf: RISC-V: Remove PERF_HES_STOPPED flag checking in riscv_pmu_start()

Since commit 096b52fd2bb4 ("perf: RISC-V: throttle perf events") the

perf_sample_event_took() function was added to report time spent in

overflow interrupts. If the interrupt takes too long, the perf framework

will lower the sysctl_perf_event_sample_rate and max_samples_per_tick.

When hwc->interrupts is larger than max_samples_per_tick, the

hwc->interrupts will be set to MAX_INTERRUPTS, and events will be

throttled within the __perf_event_account_interrupt() function.

However, the RISC-V PMU driver doesn't call riscv_pmu_stop() to update the

PERF_HES_STOPPED flag after perf_event_overflow() in pmu_sbi_ovf_handler()

function to avoid throttling. When the perf framework unthrottled the event

in the timer interrupt handler, it triggers riscv_pmu_start() function

and causes a WARN_ON_ONCE() warning, as shown below:

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/// 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