{"id":"CVE-2026-46147","state":"PUBLISHED","title":"KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()\n\nTwo bugs exist in the vCPU initialisation path:\n\n1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup\n   path jumps to 'unlock' without calling unpin_host_vcpu() or\n   unpin_host_sve_state(), permanently leaking pin references on the\n   host vCPU and SVE state pages.\n\n   Extract a register_hyp_vcpu() helper that performs the checks and\n   the store. When register_hyp_vcpu() returns an error, call\n   unpin_host_vcpu() and unpin_host_sve_state() inline before falling\n   through to the existing 'unlock' label.\n\n2. register_hyp_vcpu() publishes the new vCPU pointer into\n   'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller\n   of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU\n   object.\n\n   Ensure the store uses smp_store_release() and the load uses\n   smp_load_acquire(). While 'vm_table_lock' currently serialises the\n   store and the load, these barriers ensure the reader sees the fully\n   initialised 'hyp_vcpu' object even if there were a lockless path or\n   if the lock's own ordering guarantees were insufficient for nested\n   object initialization.","publishedAt":"2026-05-28T09:36:03.892Z","updatedAt":"2026-06-14T17:58:03.230Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"7d3c27b54253cda91dc4d2c1bfc109c490837ab9","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6d69c0ed978f7f0efd053fc98390f25ab77c1aea","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"73b9c1e5da84cd69b1a86e374e450817cd051371","versionType":"git"},{"version":"0","status":"affected","lessThan":"6.18.30","versionType":"semver"},{"version":"0","status":"affected","lessThan":"7.0.7","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]}],"references":["https://git.kernel.org/stable/c/7d3c27b54253cda91dc4d2c1bfc109c490837ab9","https://git.kernel.org/stable/c/6d69c0ed978f7f0efd053fc98390f25ab77c1aea","https://git.kernel.org/stable/c/73b9c1e5da84cd69b1a86e374e450817cd051371"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/46xxx/CVE-2026-46147.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46147","state":"PUBLISHED","datePublished":"2026-05-28T09:36:03.892Z","dateUpdated":"2026-06-14T17:58:03.230Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-13T15:03:33.101Z"},"containers":{"cna":{"title":"KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()\n\nTwo bugs exist in the vCPU initialisation path:\n\n1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup\n   path jumps to 'unlock' without calling unpin_host_vcpu() or\n   unpin_host_sve_state(), permanently leaking pin references on the\n   host vCPU and SVE state pages.\n\n   Extract a register_hyp_vcpu() helper that performs the checks and\n   the store. When register_hyp_vcpu() returns an error, call\n   unpin_host_vcpu() and unpin_host_sve_state() inline before falling\n   through to the existing 'unlock' label.\n\n2. register_hyp_vcpu() publishes the new vCPU pointer into\n   'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller\n   of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU\n   object.\n\n   Ensure the store uses smp_store_release() and the load uses\n   smp_load_acquire(). While 'vm_table_lock' currently serialises the\n   store and the load, these barriers ensure the reader sees the fully\n   initialised 'hyp_vcpu' object even if there were a lockless path or\n   if the lock's own ordering guarantees were insufficient for nested\n   object initialization."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"7d3c27b54253cda91dc4d2c1bfc109c490837ab9","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6d69c0ed978f7f0efd053fc98390f25ab77c1aea","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"73b9c1e5da84cd69b1a86e374e450817cd051371","versionType":"git"},{"version":"0","status":"affected","lessThan":"6.18.30","versionType":"semver"},{"version":"0","status":"affected","lessThan":"7.0.7","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7d3c27b54253cda91dc4d2c1bfc109c490837ab9"},{"url":"https://git.kernel.org/stable/c/6d69c0ed978f7f0efd053fc98390f25ab77c1aea"},{"url":"https://git.kernel.org/stable/c/73b9c1e5da84cd69b1a86e374e450817cd051371"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-14T17:58:03.230Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}