Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 __init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a write from EL0 reaches the trap and takes the host down without a panic message. Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9 bits.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 686d8f7b592f3466f44aea653c8147611b351c83 before bb8c90c86441c090e9036f019cf1b4d7894a2c40; affected 858c7bfcb35e1100b58bb63c9f562d86e09418d9 before 071f51188a5d8ec10535541255587976d12fc7d8; affected 858c7bfcb35e1100b58bb63c9f562d86e09418d9 before ce71865bf43f88bed9d9218e9218e537150be506; affected 858c7bfcb35e1100b58bb63c9f562d86e09418d9 before 2bc6b218717b9d08f466f88209251d54bc09b207; affected 882f78400322c0aec4b641a7168adad9a66bc0c2; affected 6.12.25 before 6.12.112; affected 6.14.4 before 6.15 |
| Linux / Linux | affected 6.15; unaffected 0 before 6.15; unaffected 6.12.112 through 6.12.*; unaffected 6.18.55 through 6.18.*; unaffected 7.2.9 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.