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CVE-2022-49781— perf/x86/amd: Fix crash due to race between amd_pmu_enable_all, perf NMI and throttling

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞,该漏洞源于竞争条件,可能导致空指针解引用。

AI Predicted 7.8 Difficulty: Hard EPSS 0.11% · P2

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 6

VendorProduct Version RangeStatus
Linux Linux ada543459cab7f653dcacdaba4011a8bb19c627c< fd5e454b856ed86b090336e269695d9908609b71 affected
ada543459cab7f653dcacdaba4011a8bb19c627c< baa014b9543c8e5e94f5d15b66abfe60750b8284 affected
5.19 affected
< 5.19 unaffected
6.0.10≤ 6.0.* unaffected
6.1≤ * unaffected
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I. Basic Information for CVE-2022-49781

Vulnerability Information

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Vulnerability Title
perf/x86/amd: Fix crash due to race between amd_pmu_enable_all, perf NMI and throttling
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: perf/x86/amd: Fix crash due to race between amd_pmu_enable_all, perf NMI and throttling amd_pmu_enable_all() does: if (!test_bit(idx, cpuc->active_mask)) continue; amd_pmu_enable_event(cpuc->events[idx]); A perf NMI of another event can come between these two steps. Perf NMI handler internally disables and enables _all_ events, including the one which nmi-intercepted amd_pmu_enable_all() was in process of enabling. If that unintentionally enabled event has very low sampling period and causes immediate successive NMI, causing the event to be throttled, cpuc->events[idx] and cpuc->active_mask gets cleared by x86_pmu_stop(). This will result in amd_pmu_enable_event() getting called with event=NULL when amd_pmu_enable_all() resumes after handling the NMIs. This causes a kernel crash: BUG: kernel NULL pointer dereference, address: 0000000000000198 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page [...] Call Trace: <TASK> amd_pmu_enable_all+0x68/0xb0 ctx_resched+0xd9/0x150 event_function+0xb8/0x130 ? hrtimer_start_range_ns+0x141/0x4a0 ? perf_duration_warn+0x30/0x30 remote_function+0x4d/0x60 __flush_smp_call_function_queue+0xc4/0x500 flush_smp_call_function_queue+0x11d/0x1b0 do_idle+0x18f/0x2d0 cpu_startup_entry+0x19/0x20 start_secondary+0x121/0x160 secondary_startup_64_no_verify+0xe5/0xeb </TASK> amd_pmu_disable_all()/amd_pmu_enable_all() calls inside perf NMI handler were recently added as part of BRS enablement but I'm not sure whether we really need them. We can just disable BRS in the beginning and enable it back while returning from NMI. This will solve the issue by not enabling those events whose active_masks are set but are not yet enabled in hw pmu.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞,该漏洞源于竞争条件,可能导致空指针解引用。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux ada543459cab7f653dcacdaba4011a8bb19c627c ~ fd5e454b856ed86b090336e269695d9908609b71 -
Linux Linux 5.19 -

II. Public POCs for CVE-2022-49781

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III. Intelligence Information for CVE-2022-49781

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Patches & Fixes for CVE-2022-49781 (2)

Same Patch Batch · Linux · 2025-05-01 · 245 CVEs total

CVE-2025-37750 9.8 CRITICAL smb: client: fix UAF in decryption with multichannel
CVE-2025-37778 9.8 CRITICAL ksmbd: Fix dangling pointer in krb_authenticate
CVE-2022-49770 9.8 CRITICAL ceph: avoid putting the realm twice when decoding snaps fails
CVE-2022-49931 8.8 HIGH IB/hfi1: Correctly move list in sc_disable()
CVE-2025-37776 8.8 HIGH ksmbd: fix use-after-free in smb_break_all_levII_oplock()
CVE-2025-37777 8.8 HIGH ksmbd: fix use-after-free in __smb2_lease_break_noti()
CVE-2025-37790 8.8 HIGH net: mctp: Set SOCK_RCU_FREE
CVE-2022-49910 8.8 HIGH Bluetooth: L2CAP: Fix use-after-free caused by l2cap_reassemble_sdu
CVE-2022-49886 8.4 HIGH x86/tdx: Panic on bad configs that #VE on "private" memory access
CVE-2025-23159 8.4 HIGH media: venus: hfi: add a check to handle OOB in sfr region
CVE-2025-37749 8.2 HIGH net: ppp: Add bound checking for skb data on ppp_sync_txmung
CVE-2025-37765 7.8 HIGH drm/nouveau: prime: fix ttm_bo_delayed_delete oops
CVE-2025-37779 7.8 HIGH lib/iov_iter: fix to increase non slab folio refcount
CVE-2022-49920 7.8 HIGH netfilter: nf_tables: netlink notifier might race to release objects
CVE-2022-49919 7.8 HIGH netfilter: nf_tables: release flow rule object from commit path
CVE-2022-49921 7.8 HIGH net: sched: Fix use after free in red_enqueue()
CVE-2025-37752 7.8 HIGH net_sched: sch_sfq: move the limit validation
CVE-2025-37756 7.8 HIGH net: tls: explicitly disallow disconnect
CVE-2025-37761 7.8 HIGH drm/xe: Fix an out-of-bounds shift when invalidating TLB
CVE-2022-49804 7.8 HIGH s390: avoid using global register for current_stack_pointer

Showing top 20 of 245 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

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