{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f316cdff8d677db9ad9c90acb44c4cd535b0ee27"
            },
            {
              "fixed": "6bb55381daf1a1bed0657189a1396e7467712525"
            },
            {
              "fixed": "160619b38707241e22569f9c983a4b3d0890996a"
            },
            {
              "fixed": "ad1bf77039cba83373bf1eff3784655e3e3ed2ab"
            },
            {
              "fixed": "6a4117eee82dd85f11bf898bf66026764011eeb6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.6.0"
            },
            {
              "fixed": "6.12.113"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.56"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98848.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nrtc: ac100: Assign .num before accessing .hws\n\nCommit f316cdff8d67 (\"clk: Annotate struct clk_hw_onecell_data with\n__counted_by\") annotated the hws member of 'struct clk_hw_onecell_data'\nwith __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS)\nabout the number of elements in .hws[], so that it can warn when .hws[]\nis accessed out of bounds. As noted in that change, the __counted_by\nmember must be initialized with the number of elements before the first\narray access happens, otherwise there will be a warning from each access\nprior to the initialization because the number of elements is zero.\nThis occurs in ac100_rtc_register_clks() due to .num being assigned only\nafter every clkout clock has been stored in .hws[]. With\nCONFIG_UBSAN_BOUNDS and a compiler that implements __counted_by (GCC\n15.1+ or Clang 20.1+), this triggers an array-index-out-of-bounds report\nduring probe, and with CONFIG_UBSAN_TRAP the first store traps.\n\nInitialize .num with AC100_CLKOUT_NUM, the number of elements .hws[] was\nallocated with, right after the allocation. That is the value the loop\ncounter ends up at on the success path anyway, so the provider's\nbehaviour is unchanged.",
  "id": "CVE-2026-98848",
  "modified": "2026-10-20T02:30:26.920257962Z",
  "published": "2026-10-18T15:50:47.105Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/160619b38707241e22569f9c983a4b3d0890996a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6a4117eee82dd85f11bf898bf66026764011eeb6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6bb55381daf1a1bed0657189a1396e7467712525"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ad1bf77039cba83373bf1eff3784655e3e3ed2ab"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98848.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98848"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "rtc: ac100: Assign .num before accessing .hws"
}