drm/xe/pt: Reset current_op in xe_pt_update_ops_init()

{
  "id": "6886bfcc38f25d03311c2fb8a3fbdda24ceed58e0e248cb579cf15dc8c70d73d",
  "url": "https://osv.dev/vulnerability/CVE-2026-68264",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "drm/xe/pt: Reset current_op in xe_pt_update_ops_init()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: drm/xe/pt: Reset current_op in xe_pt_update_ops_init() xe_pt_update_ops_init() fails to reset current_op to 0. On the vm_bind path, ops_execute() calls xe_pt_update_ops_prepare() inside the xe_validation_guard() / drm_exec_until_all_locked() loop. When that loop retries due to lock contention or OOM eviction (drm_exec_retry_on_contention() / xe_validation_retry_on_oom()), xe_pt_update_ops_prepare() runs again on the same vops, and each call to bind_op_prepare() increments current_op without resetting it. After N retries current_op exceeds the array size allocated by xe_vma_ops_alloc(), causing an out-of-bounds write into SLUB-poisoned memory and a subsequent UAF crash in xe_migrate_update_pgtables_cpu() when reading the corrupted pt_op->bind. Also reset needs_svm_lock and needs_invalidation which are derived in the same prepare pass and would otherwise cause wrong migrate ops selection and redundant TLB invalidation on retry. Fix this by resetting current_op, needs_svm_lock and needs_invalidation in xe_pt_update_ops_init(). v2 (Matt): - Add details in commit message. - Add Fixes tag and Cc to stable@vger.kernel.org (cherry picked from commit 046045543e530605c441063535e7dca0075369a6)",
    "evidence": "osv:CVE-2026-68264",
    "products": [
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          "value": "Kernel",
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        "prerequisites": [],
        "fixed_versions": [
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            "value": "6.12.103",
            "evidence": "/affected/1/ranges"
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            "evidence": "/affected/1/ranges"
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            "value": "7.1.6",
            "evidence": "/affected/1/ranges"
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    "severity": "high",
    "structured": {
      "id": "CVE-2026-68264",
      "aliases": [
        "CVE-2026-68264"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
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      ],
      "modified": "2026-10-28T02:30:25.888730394Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/157b1e3384d7d37f59c0c2b2ff2af8f557db1daa",
        "https://git.kernel.org/stable/c/6384271ac1ac0099198d15df79212a19ebdb929d",
        "https://git.kernel.org/stable/c/90e4fd331b980259c40118d05b89b0ec514e7c48",
        "https://git.kernel.org/stable/c/be5c39730ab8f1dfe59983bf7d8e3705541d1fee",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68264.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-68264",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
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  "source_id": "core-osv",
  "document_id": 492581,
  "published_at": "2026-08-10T12:01:38.686+00:00"
}