nvd-json-data-feeds/CVE-2022/CVE-2022-499xx/CVE-2022-49955.json

{
  "id": "CVE-2022-49955",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2025-06-18T11:15:22.630",
  "lastModified": "2025-06-18T13:46:52.973",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/rtas: Fix RTAS MSR[HV] handling for Cell\n\nThe semi-recent changes to MSR handling when entering RTAS (firmware)\ncause crashes on IBM Cell machines. An example trace:\n\n  kernel tried to execute user page (2fff01a8) - exploit attempt? (uid: 0)\n  BUG: Unable to handle kernel instruction fetch\n  Faulting instruction address: 0x2fff01a8\n  Oops: Kernel access of bad area, sig: 11 [#1]\n  BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 NUMA Cell\n  Modules linked in:\n  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W          6.0.0-rc2-00433-gede0a8d3307a #207\n  NIP:  000000002fff01a8 LR: 0000000000032608 CTR: 0000000000000000\n  REGS: c0000000015236b0 TRAP: 0400   Tainted: G        W           (6.0.0-rc2-00433-gede0a8d3307a)\n  MSR:  0000000008001002 <ME,RI>  CR: 00000000  XER: 20000000\n  ...\n  NIP 0x2fff01a8\n  LR  0x32608\n  Call Trace:\n    0xc00000000143c5f8 (unreliable)\n    .rtas_call+0x224/0x320\n    .rtas_get_boot_time+0x70/0x150\n    .read_persistent_clock64+0x114/0x140\n    .read_persistent_wall_and_boot_offset+0x24/0x80\n    .timekeeping_init+0x40/0x29c\n    .start_kernel+0x674/0x8f0\n    start_here_common+0x1c/0x50\n\nUnlike PAPR platforms where RTAS is only used in guests, on the IBM Cell\nmachines Linux runs with MSR[HV] set but also uses RTAS, provided by\nSLOF.\n\nFix it by copying the MSR[HV] bit from the MSR value we've just read\nusing mfmsr into the value used for RTAS.\n\nIt seems like we could also fix it using an #ifdef CELL to set MSR[HV],\nbut that doesn't work because it's possible to build a single kernel\nimage that runs on both Cell native and pseries."
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/8b08d4f97233d8e58fff2fd9d5f86397a49733c5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/91926d8b7e71aaf5f84f0cf208fc5a8b7a761050",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}