ghsa-v5xv-g87f-x57w
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: make apf token non-zero to fix bug
In current async pagefault logic, when a page is ready, KVM relies on kvm_arch_can_dequeue_async_page_present() to determine whether to deliver a READY event to the Guest. This function test token value of struct kvm_vcpu_pv_apf_data, which must be reset to zero by Guest kernel when a READY event is finished by Guest. If value is zero meaning that a READY event is done, so the KVM can deliver another. But the kvm_arch_setup_async_pf() may produce a valid token with zero value, which is confused with previous mention and may lead the loss of this READY event.
This bug may cause task blocked forever in Guest: INFO: task stress:7532 blocked for more than 1254 seconds. Not tainted 5.10.0 #16 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:stress state:D stack: 0 pid: 7532 ppid: 1409 flags:0x00000080 Call Trace: __schedule+0x1e7/0x650 schedule+0x46/0xb0 kvm_async_pf_task_wait_schedule+0xad/0xe0 ? exit_to_user_mode_prepare+0x60/0x70 __kvm_handle_async_pf+0x4f/0xb0 ? asm_exc_page_fault+0x8/0x30 exc_page_fault+0x6f/0x110 ? asm_exc_page_fault+0x8/0x30 asm_exc_page_fault+0x1e/0x30 RIP: 0033:0x402d00 RSP: 002b:00007ffd31912500 EFLAGS: 00010206 RAX: 0000000000071000 RBX: ffffffffffffffff RCX: 00000000021a32b0 RDX: 000000000007d011 RSI: 000000000007d000 RDI: 00000000021262b0 RBP: 00000000021262b0 R08: 0000000000000003 R09: 0000000000000086 R10: 00000000000000eb R11: 00007fefbdf2baa0 R12: 0000000000000000 R13: 0000000000000002 R14: 000000000007d000 R15: 0000000000001000
{
"affected": [],
"aliases": [
"CVE-2022-48943"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-08-22T04:15:19Z",
"severity": "HIGH"
},
"details": "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 \u003e /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",
"id": "GHSA-v5xv-g87f-x57w",
"modified": "2024-08-22T18:31:21Z",
"published": "2024-08-22T06:30:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-48943"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4c3644b6c96c5daa5149e5abddc07234eea47c7c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/62040f5cd7d937de547836e747b6aa8212fec573"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6f3c1fc53d86d580d8d6d749c4af23705e4f6f79"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/72fdfc75d4217b32363cc80def3de2cb3fef3f02"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
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