{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98464", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.350Z", "datePublished": "2026-10-18T15:15:16.624Z", "dateUpdated": "2026-10-19T09:20:02.501Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:20:02.501Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRISC-V: KVM: Synchronize hrtimer callback during teardown\n\nThe non-Sstc hrtimer callback clears next_set before its final uses of\nthe enclosing vCPU. If teardown observes next_set as false while the\ncallback is still running, kvm_riscv_vcpu_timer_cancel() skips\nhrtimer_cancel() and kvm_destroy_vcpus() can free the vCPU before the\ncallback enters kvm_riscv_vcpu_set_interrupt().\n\nA guest can arm the timer with SBI TIME and request shutdown with SBI\nlegacy shutdown or SRST. A VMM that honors KVM_EXIT_SYSTEM_EVENT and\ndestroys the VM supplies the teardown side of the race; no post-launch\nhost ioctl is needed to arm or request teardown.\n\nOn upstream master 62cc90241548, generic KASAN reported:\n\n BUG: KASAN: slab-use-after-free in do_raw_spin_lock\n Write of size 4 at addr ff60000005e58898\n\n kvm_riscv_vcpu_set_interrupt\n kvm_riscv_vcpu_hrtimer_expired\n __hrtimer_run_queues\n hrtimer_interrupt\n\nThe object was allocated by KVM_CREATE_VCPU and freed concurrently by:\n\n kvm_destroy_vcpus\n kvm_arch_destroy_vm\n kvm_destroy_vm\n __fput\n\nFor deterministic validation, I added mdelay(1000) immediately after\nthe existing next_set = false assignment. This only widens the\nexisting post-clear callback window. A no-delay trace build naturally\nreached the callback-after-teardown-start/before-deinit ordering in 12\nof 200 runs, but 1,500 stock-kernel stress iterations did not produce a\nKASAN report, so natural reproduction is timing-sensitive.\n\nAlways invoke hrtimer_cancel() for an initialized timer. Preserve the\nexisting -EINVAL result when the timer is no longer set, but only after\nsynchronizing with a running callback.\n\nWith this patch, hrtimer_cancel() blocked for the full widened callback\nwindow before vCPU destruction. KASAN reported no error in 100\nfixed-and-widened runs or 200 fix-only timing-sweep runs." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/riscv/kvm/vcpu_timer.c" ], "versions": [ { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "9bdbae64ae0dab93041ebc57ec4e93def793fc2d", "status": "affected", "versionType": "git" }, { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "2af03b606aadaaeb386658ef798c79bdcdef87c1", "status": "affected", "versionType": "git" }, { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "e66aced74f0122380603c9910a71d77618b28f0e", "status": "affected", "versionType": "git" }, { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "ea91f05a55b807ead3166546a2c75f4185ca645f", "status": "affected", "versionType": "git" }, { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "3cc6184bd5920c9685d87f4e260568feba08650d", "status": "affected", "versionType": "git" }, { "version": "3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22", "lessThan": "aaad136d56d91252517272b68cd533e5714698d5", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/riscv/kvm/vcpu_timer.c" ], "versions": [ { "version": "5.16", "status": "affected" }, { "version": "0", "lessThan": "5.16", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9bdbae64ae0dab93041ebc57ec4e93def793fc2d" }, { "url": "https://git.kernel.org/stable/c/2af03b606aadaaeb386658ef798c79bdcdef87c1" }, { "url": "https://git.kernel.org/stable/c/e66aced74f0122380603c9910a71d77618b28f0e" }, { "url": "https://git.kernel.org/stable/c/ea91f05a55b807ead3166546a2c75f4185ca645f" }, { "url": "https://git.kernel.org/stable/c/3cc6184bd5920c9685d87f4e260568feba08650d" }, { "url": "https://git.kernel.org/stable/c/aaad136d56d91252517272b68cd533e5714698d5" } ], "title": "RISC-V: KVM: Synchronize hrtimer callback during teardown", "x_generator": { "engine": "bippy-1.2.0" } } } }