{"id":"CVE-2022-48897","state":"PUBLISHED","title":"arm64/mm: fix incorrect file_map_count for invalid pmd","description":"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.","publishedAt":"2024-08-21T06:10:29.785Z","updatedAt":"2026-05-11T18:49:17.939Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"42b2547137f5c974bb1bfd657c869fe96b96d86f","status":"affected","lessThan":"21e5eca0ac9046da9918a919bc92b7b5a78d27e7","versionType":"git"},{"version":"42b2547137f5c974bb1bfd657c869fe96b96d86f","status":"affected","lessThan":"74c2f81054510d45b813548cb0a1c4ebf87cdd5f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/pgtable.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.19","versionType":"semver"},{"version":"6.1.7","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/pgtable.h"]}],"references":["https://git.kernel.org/stable/c/21e5eca0ac9046da9918a919bc92b7b5a78d27e7","https://git.kernel.org/stable/c/74c2f81054510d45b813548cb0a1c4ebf87cdd5f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/48xxx/CVE-2022-48897.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-48897","state":"PUBLISHED","datePublished":"2024-08-21T06:10:29.785Z","dateUpdated":"2026-05-11T18:49:17.939Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-08-21T06:06:23.291Z"},"containers":{"cna":{"title":"arm64/mm: fix incorrect file_map_count for invalid pmd","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":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"42b2547137f5c974bb1bfd657c869fe96b96d86f","status":"affected","lessThan":"21e5eca0ac9046da9918a919bc92b7b5a78d27e7","versionType":"git"},{"version":"42b2547137f5c974bb1bfd657c869fe96b96d86f","status":"affected","lessThan":"74c2f81054510d45b813548cb0a1c4ebf87cdd5f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/pgtable.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.19","versionType":"semver"},{"version":"6.1.7","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/pgtable.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/21e5eca0ac9046da9918a919bc92b7b5a78d27e7"},{"url":"https://git.kernel.org/stable/c/74c2f81054510d45b813548cb0a1c4ebf87cdd5f"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T18:49:17.939Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.1.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2022-48897","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T16:04:02.667738Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-09-12T17:33:12.803Z"}}]}}}