{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  ptp: netc: fix period truncation and potential divide-by-zero in PEROUT  The max_period bound in net_timer_enable_perout() was computed as:    max_period = (u64)NETC_TMR_DEFAULT_FIPER + integral_period;  which exceeds U32_MAX when integral_period \u003e 0 (e.g. 0x100000002 for the default 333333333 Hz clock). A period_ns that passes this check but exceeds U32_MAX is then silently truncated when stored into the u32 struct netc_pp::period field.  A truncated value of zero can reach netc_timer_set_perout_alarm(), where the local u32 period variable would also be 0, causing a divide-by-zero in roundup_u64(delta, period) whenever the stime \u003c min_time branch is taken (which always happens for a start time of {0, 0}).  Additionally, netc_timer_enable_periodic_pulse() and netc_timer_enable_fiper() both compute:    fiper = pp-\u003eperiod - integral_period;  A zero pp-\u003eperiod results in an unsigned wraparound to 0xFFFFFFFD, mis-programming the FIPER hardware register.  Fix all three issues by capping max_period at NETC_TMR_DEFAULT_FIPER (0xFFFFFFFF). This ensures that any period_ns passing the range check fits in a u32 without truncation, so the stored value is always valid and non-zero. The accepted range is reduced by integral_period ns (typically only a few nanoseconds), which is negligible in practice.",
  "id": "DEBIAN-CVE-2026-90100",
  "modified": "2026-09-18T04:47:39.014096660Z",
  "published": "2026-09-17T17:17:01.680Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-90100"
    }
  ],
  "upstream": [
    "CVE-2026-90100"
  ]
}