{"id":"CVE-2026-97587","state":"PUBLISHED","title":"perf: RISC-V: store available counter mask as bitmap","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: RISC-V: store available counter mask as bitmap\n\nThe available-counter mask was a single unsigned long, but iteration\nuses RISCV_MAX_COUNTERS, which is 64. On RV32 that reads past the object.\nFilling with an unsigned-long bit at index 32 and above is also wrong.\n\nUse DECLARE_BITMAP and set_bit/bitmap helpers. Walk each bitmap word\ninto CFG_MATCH when checking events, when allocating an index, and when\nstopping all counters. Set the counter base to i times BITS_PER_LONG.\nShare the CFG_MATCH ecall through a small helper so the 32-bit argument\nsplit is not duplicated. On qemu-system-riscv32 the probe bitmap has bits\nabove XLEN set, so the first word alone is not enough.\n\n[pjw@kernel.org: updated to apply; fixed checkpatch.pl issues]","publishedAt":"2026-09-25T10:22:06.177Z","updatedAt":"2026-10-30T12:37:30.665Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"433249a4de52ecda40ffa9c466cec1312e62826f","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"5a1b6379eed5b13eac0228b605b0bed988e547e9","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"143668c424772979a45118dc9cc9c2c13a35f41d","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"9bec7beaed074bcae4181fde9ff9dfbe4e7b0957","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"e5481db31f4654e9a1254d5d467d9b1ff2f8b1cb","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"6809da6e9c08ccc9a09cb0a48c61471679274aaa","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/perf/riscv_pmu_legacy.c","drivers/perf/riscv_pmu_sbi.c","include/linux/perf/riscv_pmu.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.18","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/perf/riscv_pmu_legacy.c","drivers/perf/riscv_pmu_sbi.c","include/linux/perf/riscv_pmu.h"]}],"references":["https://git.kernel.org/stable/c/433249a4de52ecda40ffa9c466cec1312e62826f","https://git.kernel.org/stable/c/5a1b6379eed5b13eac0228b605b0bed988e547e9","https://git.kernel.org/stable/c/143668c424772979a45118dc9cc9c2c13a35f41d","https://git.kernel.org/stable/c/9bec7beaed074bcae4181fde9ff9dfbe4e7b0957","https://git.kernel.org/stable/c/e5481db31f4654e9a1254d5d467d9b1ff2f8b1cb","https://git.kernel.org/stable/c/6809da6e9c08ccc9a09cb0a48c61471679274aaa"],"weaknesses":[],"ingestedAt":"2026-10-30T12:56:04.490Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/97xxx/CVE-2026-97587.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-97587","state":"PUBLISHED","datePublished":"2026-09-25T10:22:06.177Z","dateUpdated":"2026-10-30T12:37:30.665Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-24T16:01:01.157Z"},"containers":{"cna":{"title":"perf: RISC-V: store available counter mask as bitmap","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf: RISC-V: store available counter mask as bitmap\n\nThe available-counter mask was a single unsigned long, but iteration\nuses RISCV_MAX_COUNTERS, which is 64. On RV32 that reads past the object.\nFilling with an unsigned-long bit at index 32 and above is also wrong.\n\nUse DECLARE_BITMAP and set_bit/bitmap helpers. Walk each bitmap word\ninto CFG_MATCH when checking events, when allocating an index, and when\nstopping all counters. Set the counter base to i times BITS_PER_LONG.\nShare the CFG_MATCH ecall through a small helper so the 32-bit argument\nsplit is not duplicated. On qemu-system-riscv32 the probe bitmap has bits\nabove XLEN set, so the first word alone is not enough.\n\n[pjw@kernel.org: updated to apply; fixed checkpatch.pl issues]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"433249a4de52ecda40ffa9c466cec1312e62826f","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"5a1b6379eed5b13eac0228b605b0bed988e547e9","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"143668c424772979a45118dc9cc9c2c13a35f41d","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"9bec7beaed074bcae4181fde9ff9dfbe4e7b0957","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"e5481db31f4654e9a1254d5d467d9b1ff2f8b1cb","versionType":"git"},{"version":"e9991434596f5373dfd75857b445eb92a9253c56","status":"affected","lessThan":"6809da6e9c08ccc9a09cb0a48c61471679274aaa","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/perf/riscv_pmu_legacy.c","drivers/perf/riscv_pmu_sbi.c","include/linux/perf/riscv_pmu.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.18","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/perf/riscv_pmu_legacy.c","drivers/perf/riscv_pmu_sbi.c","include/linux/perf/riscv_pmu.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/433249a4de52ecda40ffa9c466cec1312e62826f"},{"url":"https://git.kernel.org/stable/c/5a1b6379eed5b13eac0228b605b0bed988e547e9"},{"url":"https://git.kernel.org/stable/c/143668c424772979a45118dc9cc9c2c13a35f41d"},{"url":"https://git.kernel.org/stable/c/9bec7beaed074bcae4181fde9ff9dfbe4e7b0957"},{"url":"https://git.kernel.org/stable/c/e5481db31f4654e9a1254d5d467d9b1ff2f8b1cb"},{"url":"https://git.kernel.org/stable/c/6809da6e9c08ccc9a09cb0a48c61471679274aaa"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:37:30.665Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}