CVE-2026-89815

{
  "id": "CVE-2026-89815",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:16:46.720",
  "lastModified": "2026-10-19T09:18:25.317",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/ttm: Drop tt->restore after successful restore\n\nttm_pool_restore_and_alloc() can successfully complete the restore\nprocess via ttm_pool_restore_commit(), but tt->restore is not dropped\nafterward. As a result, subsequent backup/restore flows observe what\nappears to be a completed restore, while in reality shmem handles are\nstill installed in tt->pages, leading to the stack trace below.\n\nFix this by freeing and dropping tt->restore in\nttm_pool_restore_and_alloc() upon successful completion of the restore.\n\n20545 [  309.784531] RIP: 0010:sg_alloc_append_table_from_pages+0x38c/0x490\n20547 [  309.809570] RSP: 0018:ffffc9000623b838 EFLAGS: 00010206\n20548 [  309.814827] RAX: 0000000000001000 RBX: ffff88816e42a160 RCX: 0000000000000000\n20549 [  309.821986] RDX: 0000000000002000 RSI: 0000000000000003 RDI: 0000000000001000\n20550 [  309.829147] RBP: ffff88816e42a168 R08: 0000000000000002 R09: 000000007ffff000\n20551 [  309.836310] R10: ffffc9000623b928 R11: 0000000000000000 R12: 000000007ffff000\n20552 [  309.843471] R13: ffff88815ba5a100 R14: 0000000000000000 R15: 0000000000000001\n20553 [  309.850634] FS:  00007f9ff305e700(0000) GS:ffff888276c94000(0000) knlGS:0000000000000000\n20554 [  309.858749] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n20555 [  309.864519] CR2: 00007f9fca701000 CR3: 00000001565e2005 CR4: 0000000008f70ef0\n20556 [  309.871678] PKRU: 55555558\n20557 [  309.874403] Call Trace:\n20558 [  309.876866]  <TASK>\n20559 [  309.878988]  sg_alloc_table_from_pages_segment+0x60/0x100\n20560 [  309.884415]  ? ttm_resource_manager_usage+0x36/0x60 [ttm]\n20561 [  309.889845]  ? xe_tt_map_sg+0x7d/0xd0 [xe]\n20562 [  309.894045]  xe_tt_map_sg+0x7d/0xd0 [xe]\n20563 [  309.898037]  xe_bo_move+0x927/0xaa0 [xe]\n20564 [  309.902029]  ttm_bo_handle_move_mem+0xba/0x170 [ttm]\n20565 [  309.907022]  ttm_bo_validate+0xbe/0x190 [ttm]\n20566 [  309.911405]  xe_bo_validate+0x9a/0x120 [xe]\n20567 [  309.915663]  xe_gpuvm_validate+0xd9/0x140 [xe]\n20568 [  309.920206]  drm_gpuvm_validate+0x2f0/0x5b0 [drm_gpuvm]\n20569 [  309.925459]  ? drm_exec_lock_obj+0x63/0x210 [drm_exec]\n20570 [  309.930627]  xe_vm_validate_rebind+0x46/0xb0 [xe]\n20571 [  309.935428]  xe_exec_fn+0x20/0x40 [xe]\n20572 [  309.939249]  drm_gpuvm_exec_lock+0x78/0xc0 [drm_gpuvm]\n20573 [  309.944410]  xe_validation_exec_lock+0x5a/0xa0 [xe]\n20574 [  309.949385]  xe_exec_ioctl+0x806/0xc30 [xe]\n20575 [  309.953639]  ? ttwu_queue_wakelist+0xd9/0xf0\n20576 [  309.957935]  ? __pfx_xe_exec_fn+0x10/0x10 [xe]\n20577 [  309.962449]  ? __wake_up_common+0x73/0xa0\n20578 [  309.966482]  ? __pfx_xe_exec_ioctl+0x10/0x10 [xe]\n20579 [  309.971263]  drm_ioctl_kernel+0xa3/0x100\n20580 [  309.975209]  drm_ioctl+0x213/0x440\n20581 [  309.978637]  ? __pfx_xe_exec_ioctl+0x10/0x10 [xe]\n20582 [  309.983415]  xe_drm_ioctl+0x67/0xd0 [xe]\n20583 [  309.987408]  __x64_sys_ioctl+0x7f/0xd0"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/ttm/ttm_pool.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "b63d715b8090aed48bdef5930625946fa4c0d324",
              "lessThan": "329ddc5d438f991f49e4fd24c704d1c7288d5e03",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "b63d715b8090aed48bdef5930625946fa4c0d324",
              "lessThan": "a46ab76b6cf5478e2ac7b942a377c7a1827b436a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "b63d715b8090aed48bdef5930625946fa4c0d324",
              "lessThan": "941ac10529b3be5965a88d432a161ab459672ba8",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/gpu/drm/ttm/ttm_pool.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.15",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.15",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/329ddc5d438f991f49e4fd24c704d1c7288d5e03",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/941ac10529b3be5965a88d432a161ab459672ba8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a46ab76b6cf5478e2ac7b942a377c7a1827b436a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}