arm64/boot: Disable trapping of PMZR_EL0 writes to EL2
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.12.112, 6.15, 6.18.55, 7.2.9
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
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.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 686d8f7b592f3466f44aea653c8147611b351c83 · fixed in bb8c90c86441c090e9036f019cf1b4d7894a2c40; From 858c7bfcb35e1100b58bb63c9f562d86e09418d9 · fixed in 071f51188a5d8ec10535541255587976d12fc7d8; From 858c7bfcb35e1100b58bb63c9f562d86e09418d9 · fixed in ce71865bf43f88bed9d9218e9218e537150be506; From 858c7bfcb35e1100b58bb63c9f562d86e09418d9 · fixed in 2bc6b218717b9d08f466f88209251d54bc09b207; From 6.12.25 · fixed in 6.12.112; From 6.14.4 · fixed in 6.15
- Linux Linux
6.15
- KernelLinux
fixed in 6.12.112; From 6.13.0 · fixed in 6.18.55; From 6.15.0 · fixed in 7.2.9