{"cve":"CVE-2024-47717","nvd":{"published":"2024-10-21T12:15:08.020","modified":"2026-06-17T07:57:37.083","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRISC-V: KVM: Don't zero-out PMU snapshot area before freeing data\n\nWith the latest Linux-6.11-rc3, the below NULL pointer crash is observed\nwhen SBI PMU snapshot is enabled for the guest and the guest is forcefully\npowered-off.\n\n  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000508\n  Oops [#1]\n  Modules linked in: kvm\n  CPU: 0 UID: 0 PID: 61 Comm: term-poll Not tainted 6.11.0-rc3-00018-g44d7178dd77a #3\n  Hardware name: riscv-virtio,qemu (DT)\n  epc : __kvm_write_guest_page+0x94/0xa6 [kvm]\n   ra : __kvm_write_guest_page+0x54/0xa6 [kvm]\n  epc : ffffffff01590e98 ra : ffffffff01590e58 sp : ffff8f80001f39b0\n   gp : ffffffff81512a60 tp : ffffaf80024872c0 t0 : ffffaf800247e000\n   t1 : 00000000000007e0 t2 : 0000000000000000 s0 : ffff8f80001f39f0\n   s1 : 00007fff89ac4000 a0 : ffffffff015dd7e8 a1 : 0000000000000086\n   a2 : 0000000000000000 a3 : ffffaf8000000000 a4 : ffffaf80024882c0\n   a5 : 0000000000000000 a6 : ffffaf800328d780 a7 : 00000000000001cc\n   s2 : ffffaf800197bd00 s3 : 00000000000828c4 s4 : ffffaf800248c000\n   s5 : ffffaf800247d000 s6 : 0000000000001000 s7 : 0000000000001000\n   s8 : 0000000000000000 s9 : 00007fff861fd500 s10: 0000000000000001\n   s11: 0000000000800000 t3 : 00000000000004d3 t4 : 00000000000004d3\n   t5 : ffffffff814126e0 t6 : ffffffff81412700\n  status: 0000000200000120 badaddr: 0000000000000508 cause: 000000000000000d\n  [<ffffffff01590e98>] __kvm_write_guest_page+0x94/0xa6 [kvm]\n  [<ffffffff015943a6>] kvm_vcpu_write_guest+0x56/0x90 [kvm]\n  [<ffffffff015a175c>] kvm_pmu_clear_snapshot_area+0x42/0x7e [kvm]\n  [<ffffffff015a1972>] kvm_riscv_vcpu_pmu_deinit.part.0+0xe0/0x14e [kvm]\n  [<ffffffff015a2ad0>] kvm_riscv_vcpu_pmu_deinit+0x1a/0x24 [kvm]\n  [<ffffffff0159b344>] kvm_arch_vcpu_destroy+0x28/0x4c [kvm]\n  [<ffffffff0158e420>] kvm_destroy_vcpus+0x5a/0xda [kvm]\n  [<ffffffff0159930c>] kvm_arch_destroy_vm+0x14/0x28 [kvm]\n  [<ffffffff01593260>] kvm_destroy_vm+0x168/0x2a0 [kvm]\n  [<ffffffff015933d4>] kvm_put_kvm+0x3c/0x58 [kvm]\n  [<ffffffff01593412>] kvm_vm_release+0x22/0x2e [kvm]\n\nClearly, the kvm_vcpu_write_guest() function is crashing because it is\nbeing called from kvm_pmu_clear_snapshot_area() upon guest tear down.\n\nTo address the above issue, simplify the kvm_pmu_clear_snapshot_area() to\nnot zero-out PMU snapshot area from kvm_pmu_clear_snapshot_area() because\nthe guest is anyway being tore down.\n\nThe kvm_pmu_clear_snapshot_area() is also called when guest changes\nPMU snapshot area of a VCPU but even in this case the previous PMU\nsnaphsot area must not be zeroed-out because the guest might have\nreclaimed the pervious PMU snapshot area for some other purpose.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/47d40d93292d9cff8dabb735bed83d930fa03950","https://git.kernel.org/stable/c/6d0a5dcfc78bd18f2abb9641f83380135494559b","https://git.kernel.org/stable/c/81aa95fd5bd14ff49617f07fa79a8d1f1cf2ce9a"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:56:33.105311382+00:00"},"epss":{"cve":"CVE-2024-47717","score":0.00216,"percentile":0.12028,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}