{
   "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/mmu: make apf token non-zero to fix bug\n\nIn current async pagefault logic, when a page is ready, KVM relies on\nkvm_arch_can_dequeue_async_page_present() to determine whether to deliver\na READY event to the Guest. This function test token value of struct\nkvm_vcpu_pv_apf_data, which must be reset to zero by Guest kernel when a\nREADY event is finished by Guest. If value is zero meaning that a READY\nevent is done, so the KVM can deliver another.\nBut the kvm_arch_setup_async_pf() may produce a valid token with zero\nvalue, which is confused with previous mention and may lead the loss of\nthis READY event.\n\nThis bug may cause task blocked forever in Guest:\n INFO: task stress:7532 blocked for more than 1254 seconds.\n       Not tainted 5.10.0 #16\n \"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\" disables this message.\n task:stress          state:D stack:    0 pid: 7532 ppid:  1409\n flags:0x00000080\n Call Trace:\n  __schedule+0x1e7/0x650\n  schedule+0x46/0xb0\n  kvm_async_pf_task_wait_schedule+0xad/0xe0\n  ? exit_to_user_mode_prepare+0x60/0x70\n  __kvm_handle_async_pf+0x4f/0xb0\n  ? asm_exc_page_fault+0x8/0x30\n  exc_page_fault+0x6f/0x110\n  ? asm_exc_page_fault+0x8/0x30\n  asm_exc_page_fault+0x1e/0x30\n RIP: 0033:0x402d00\n RSP: 002b:00007ffd31912500 EFLAGS: 00010206\n RAX: 0000000000071000 RBX: ffffffffffffffff RCX: 00000000021a32b0\n RDX: 000000000007d011 RSI: 000000000007d000 RDI: 00000000021262b0\n RBP: 00000000021262b0 R08: 0000000000000003 R09: 0000000000000086\n R10: 00000000000000eb R11: 00007fefbdf2baa0 R12: 0000000000000000\n R13: 0000000000000002 R14: 000000000007d000 R15: 0000000000001000"
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/x86/kvm/mmu/mmu.c"
               ],
               "versions": [
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "72fdfc75d421",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "4c3644b6c96c",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "62040f5cd7d9",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "6f3c1fc53d86",
                     "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/mmu/mmu.c"
               ],
               "versions": [
                  {
                     "version": "5.10.103",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.26",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.16.12",
                     "lessThanOrEqual": "5.16.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.17",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/72fdfc75d4217b32363cc80def3de2cb3fef3f02"
            },
            {
               "url": "https://git.kernel.org/stable/c/4c3644b6c96c5daa5149e5abddc07234eea47c7c"
            },
            {
               "url": "https://git.kernel.org/stable/c/62040f5cd7d937de547836e747b6aa8212fec573"
            },
            {
               "url": "https://git.kernel.org/stable/c/6f3c1fc53d86d580d8d6d749c4af23705e4f6f79"
            }
         ],
         "title": "KVM: x86/mmu: make apf token non-zero to fix bug",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2022-48943",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
