{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\n\nKASAN reports the following issue:\n\n BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\n\n CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G               X --------- ---\n Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\n Call Trace:\n  dump_stack+0xa5/0xe6\n  print_address_description.constprop.0+0x18/0x130\n  ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  __kasan_report.cold+0x7f/0x114\n  ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  kasan_report+0x38/0x50\n  kasan_check_range+0xf5/0x1d0\n  kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n  ? kvm_arch_exit+0x110/0x110 [kvm]\n  ? sched_clock+0x5/0x10\n  ioapic_write_indirect+0x59f/0x9e0 [kvm]\n  ? static_obj+0xc0/0xc0\n  ? __lock_acquired+0x1d2/0x8c0\n  ? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\n\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs)."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/x86/kvm/ioapic.c"
               ],
               "versions": [
                  {
                     "version": "7ee30bc132c6",
                     "lessThan": "bebabb76ad9a",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "7ee30bc132c6",
                     "lessThan": "99a9e9b80f19",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "7ee30bc132c6",
                     "lessThan": "2f9b68f57c62",
                     "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/x86/kvm/ioapic.c"
               ],
               "versions": [
                  {
                     "version": "5.5",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.5",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.10.71",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.14.10",
                     "lessThanOrEqual": "5.14.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b"
            },
            {
               "url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792"
            },
            {
               "url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69"
            }
         ],
         "title": "KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47390",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
