{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2022-48689",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2022-48689",
    "idYear": 2022,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-03T15:00:02.083Z",
    "updatedAt": "2026-05-11T18:45:03.597Z",
    "importedAt": "2026-10-24T01:56:45.230Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "tcp: TX zerocopy should not sense pfmemalloc status",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: TX zerocopy should not sense pfmemalloc status\n\nWe got a recent syzbot report [1] showing a possible misuse\nof pfmemalloc page status in TCP zerocopy paths.\n\nIndeed, for pages coming from user space or other layers,\nusing page_is_pfmemalloc() is moot, and possibly could give\nfalse positives.\n\nThere has been attempts to make page_is_pfmemalloc() more robust,\nbut not using it in the first place in this context is probably better,\nremoving cpu cycles.\n\nNote to stable teams :\n\nYou need to backport 84ce071e38a6 (\"net: introduce\n__skb_fill_page_desc_noacc\") as a prereq.\n\nRace is more probable after commit c07aea3ef4d4\n(\"mm: add a signature in struct page\") because page_is_pfmemalloc()\nis now using low order bit from page->lru.next, which can change\nmore often than page->index.\n\nLow order bit should never be set for lru.next (when used as an anchor\nin LRU list), so KCSAN report is mostly a false positive.\n\nBackporting to older kernel versions seems not necessary.\n\n[1]\nBUG: KCSAN: data-race in lru_add_fn / tcp_build_frag\n\nwrite to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0:\n__list_add include/linux/list.h:73 [inline]\nlist_add include/linux/list.h:88 [inline]\nlruvec_add_folio include/linux/mm_inline.h:105 [inline]\nlru_add_fn+0x440/0x520 mm/swap.c:228\nfolio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246\nfolio_batch_add_and_move mm/swap.c:263 [inline]\nfolio_add_lru+0xf1/0x140 mm/swap.c:490\nfilemap_add_folio+0xf8/0x150 mm/filemap.c:948\n__filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981\npagecache_get_page+0x26/0x190 mm/folio-compat.c:104\ngrab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116\next4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988\ngeneric_perform_write+0x1d4/0x3f0 mm/filemap.c:3738\next4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270\next4_file_write_iter+0x2e3/0x1210\ncall_write_iter include/linux/fs.h:2187 [inline]\nnew_sync_write fs/read_write.c:491 [inline]\nvfs_write+0x468/0x760 fs/read_write.c:578\nksys_write+0xe8/0x1a0 fs/read_write.c:631\n__do_sys_write fs/read_write.c:643 [inline]\n__se_sys_write fs/read_write.c:640 [inline]\n__x64_sys_write+0x3e/0x50 fs/read_write.c:640\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nread to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1:\npage_is_pfmemalloc include/linux/mm.h:1740 [inline]\n__skb_fill_page_desc include/linux/skbuff.h:2422 [inline]\nskb_fill_page_desc include/linux/skbuff.h:2443 [inline]\ntcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018\ndo_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075\ntcp_sendpage_locked net/ipv4/tcp.c:1140 [inline]\ntcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150\ninet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833\nkernel_sendpage+0x184/0x300 net/socket.c:3561\nsock_sendpage+0x5a/0x70 net/socket.c:1054\npipe_to_sendpage+0x128/0x160 fs/splice.c:361\nsplice_from_pipe_feed fs/splice.c:415 [inline]\n__splice_from_pipe+0x222/0x4d0 fs/splice.c:559\nsplice_from_pipe fs/splice.c:594 [inline]\ngeneric_splice_sendpage+0x89/0xc0 fs/splice.c:743\ndo_splice_from fs/splice.c:764 [inline]\ndirect_splice_actor+0x80/0xa0 fs/splice.c:931\nsplice_direct_to_actor+0x305/0x620 fs/splice.c:886\ndo_splice_direct+0xfb/0x180 fs/splice.c:974\ndo_sendfile+0x3bf/0x910 fs/read_write.c:1249\n__do_sys_sendfile64 fs/read_write.c:1317 [inline]\n__se_sys_sendfile64 fs/read_write.c:1303 [inline]\n__x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nvalue changed: 0x0000000000000000 -> 0xffffea0004a1d288\n\nReported by Kernel Concurrency Sanitizer on:\nCPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "c07aea3ef4d4076f18f567b98ed01e082e02ed51",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8527c9a6bf8e54fef0a8d3d7d8874a48c725c915"
            },
            {
              "version": "c07aea3ef4d4076f18f567b98ed01e082e02ed51",
              "status": "affected",
              "versionType": "git",
              "lessThan": "6730c48ed6b0cd939fc9b30b2d621ce0b89bea83"
            },
            {
              "version": "c07aea3ef4d4076f18f567b98ed01e082e02ed51",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3261400639463a853ba2b3be8bd009c2a8089775"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.14",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.14"
            },
            {
              "version": "5.15.68",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.19.9",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.19.*"
            },
            {
              "version": "6.0",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}