{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-90386",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-90386"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "i3c: dw: avoid shift-out-of-bounds when DAA assigns no devices",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: dw: avoid shift-out-of-bounds when DAA assigns no devices\n\nOn an empty bus ENTDAA assigns nothing, so cmd->rx_len (the count\nof addresses left unassigned) equals master->maxdevs.\n\nThe GENMASK() index master->maxdevs - cmd->rx_len - 1 then becomes -1,\nwhich trips up UBSAN. This happens every time on boot on a Gigabyte/AMD\nserver:\n\n    UBSAN: shift-out-of-bounds in drivers/i3c/master/dw-i3c-master.c:905:12\n    shift exponent 64 is too large for 64-bit type 'long unsigned int'\n    CPU: 7 UID: 0 PID: 963 Comm: (udev-worker) Not tainted 7.0.11-200.fc44.x86_64 #1 PREEMPT(lazy)\n    Hardware name: Giga Computing E163-Z34-AAH1-000/MZ33-DC1-000, BIOS R32_F45 04/01/2026\n    Call Trace:\n     <TASK>\n     dump_stack_lvl+0x5d/0x80\n     ubsan_epilogue+0x5/0x2b\n     __ubsan_handle_shift_out_of_bounds.cold+0xd7/0x1ab\n     dw_i3c_master_daa.cold+0x1b/0x96 [dw_i3c_master]\n     i3c_master_do_daa_ext.part.0+0x3e/0xf0 [i3c]\n\nSkip the mask when no new device was assigned.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.188",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-90386"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5650b013e6bfc14c8b30be727f4a715b01860a08"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/63110ccc434e10d9e9d2c7d82ebfa8a6f9cedd94"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/3a1c35739efb69e8ec2a868113a0471a01bb8f29"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/111f559e5b6461f5f6977275716e6c5d1eb7ea27"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/754533e6169d1f10bdef7a6ba9bd7740b524e1d4"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9eaac0cb4ca94e2e32c53c156ae5b813ba7ef90c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/618dd640ded6b94bbdb79c798a901ec564797033"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/038cf48b3170af26a70bf2dee4f8c3ac910f5176"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-17T16:10:40Z"
  }
}