{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64/mm: fix incorrect file_map_count for invalid pmd\n\nThe page table check trigger BUG_ON() unexpectedly when split hugepage:\n\n ------------[ cut here ]------------\n kernel BUG at mm/page_table_check.c:119!\n Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n Dumping ftrace buffer:\n    (ftrace buffer empty)\n Modules linked in:\n CPU: 7 PID: 210 Comm: transhuge-stres Not tainted 6.1.0-rc3+ #748\n Hardware name: linux,dummy-virt (DT)\n pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n pc : page_table_check_set.isra.0+0x398/0x468\n lr : page_table_check_set.isra.0+0x1c0/0x468\n[...]\n Call trace:\n  page_table_check_set.isra.0+0x398/0x468\n  __page_table_check_pte_set+0x160/0x1c0\n  __split_huge_pmd_locked+0x900/0x1648\n  __split_huge_pmd+0x28c/0x3b8\n  unmap_page_range+0x428/0x858\n  unmap_single_vma+0xf4/0x1c8\n  zap_page_range+0x2b0/0x410\n  madvise_vma_behavior+0xc44/0xe78\n  do_madvise+0x280/0x698\n  __arm64_sys_madvise+0x90/0xe8\n  invoke_syscall.constprop.0+0xdc/0x1d8\n  do_el0_svc+0xf4/0x3f8\n  el0_svc+0x58/0x120\n  el0t_64_sync_handler+0xb8/0xc0\n  el0t_64_sync+0x19c/0x1a0\n[...]\n\nOn arm64, pmd_leaf() will return true even if the pmd is invalid due to\npmd_present_invalid() check. So in pmdp_invalidate() the file_map_count\nwill not only decrease once but also increase once. Then in set_pte_at(),\nthe file_map_count increase again, and so trigger BUG_ON() unexpectedly.\n\nAdd !pmd_present_invalid() check in pmd_user_accessible_page() to fix the\nproblem."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/arm64/include/asm/pgtable.h"
               ],
               "versions": [
                  {
                     "version": "42b2547137f5",
                     "lessThan": "21e5eca0ac90",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "42b2547137f5",
                     "lessThan": "74c2f8105451",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "arch/arm64/include/asm/pgtable.h"
               ],
               "versions": [
                  {
                     "version": "5.19",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.19",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.1.7",
                     "lessThanOrEqual": "6.1.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.2",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/21e5eca0ac9046da9918a919bc92b7b5a78d27e7"
            },
            {
               "url": "https://git.kernel.org/stable/c/74c2f81054510d45b813548cb0a1c4ebf87cdd5f"
            }
         ],
         "title": "arm64/mm: fix incorrect file_map_count for invalid pmd",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2022-48897",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}