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CVE-2026-90386

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: i3c: dw: avoid shift-out-of-bounds when DAA assigns no devices On an empty bus ENTDAA assigns nothing, so cmd->rx_len (the count of addresses left unassigned) equals master->maxdevs. The GENMASK() index master->maxdevs - cmd->rx_len - 1 then becomes -1, which trips up UBSAN. This happens every time on boot on a Gigabyte/AMD server: UBSAN: shift-out-of-bounds in drivers/i3c/master/dw-i3c-master.c:905:12 shift exponent 64 is too large for 64-bit type 'long unsigned int' CPU: 7 UID: 0 PID: 963 Comm: (udev-worker) Not tainted 7.0.11-200.fc44.x86_64 #1 PREEMPT(lazy) Hardware name: Giga Computing E163-Z34-AAH1-000/MZ33-DC1-000, BIOS R32_F45 04/01/2026 Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 ubsan_epilogue+0x5/0x2b __ubsan_handle_shift_out_of_bounds.cold+0xd7/0x1ab dw_i3c_master_daa.cold+0x1b/0x96 [dw_i3c_master] i3c_master_do_daa_ext.part.0+0x3e/0xf0 [i3c] Skip the mask when no new device was assigned.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:17:37.993000
Last modified
2026-10-19 09:19:32.597000
View original CVE JSON
{
  "id": "CVE-2026-90386",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-17T17:17:37.993",
  "lastModified": "2026-10-19T09:19:32.597",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/i3c/master/dw-i3c-master.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "5650b013e6bfc14c8b30be727f4a715b01860a08",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "63110ccc434e10d9e9d2c7d82ebfa8a6f9cedd94",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "3a1c35739efb69e8ec2a868113a0471a01bb8f29",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "111f559e5b6461f5f6977275716e6c5d1eb7ea27",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "754533e6169d1f10bdef7a6ba9bd7740b524e1d4",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "9eaac0cb4ca94e2e32c53c156ae5b813ba7ef90c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "618dd640ded6b94bbdb79c798a901ec564797033",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef",
              "lessThan": "038cf48b3170af26a70bf2dee4f8c3ac910f5176",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/i3c/master/dw-i3c-master.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.0",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.0",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/038cf48b3170af26a70bf2dee4f8c3ac910f5176",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/111f559e5b6461f5f6977275716e6c5d1eb7ea27",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3a1c35739efb69e8ec2a868113a0471a01bb8f29",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5650b013e6bfc14c8b30be727f4a715b01860a08",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/618dd640ded6b94bbdb79c798a901ec564797033",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/63110ccc434e10d9e9d2c7d82ebfa8a6f9cedd94",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/754533e6169d1f10bdef7a6ba9bd7740b524e1d4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}