drm/sched: fix null-ptr-deref in init entity

{
  "id": "3b1ed880797385c9a82560e5bd4adda95f98b99ed2155a702f51d0a4275e315a",
  "url": "https://osv.dev/vulnerability/CVE-2024-26657",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "drm/sched: fix null-ptr-deref in init entity",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: drm/sched: fix null-ptr-deref in init entity The bug can be triggered by sending an amdgpu_cs_wait_ioctl to the AMDGPU DRM driver on any ASICs with valid context. The bug was reported by Joonkyo Jung . For example the following code: static void Syzkaller2(int fd) { union drm_amdgpu_ctx arg1; union drm_amdgpu_wait_cs arg2; arg1.in.op = AMDGPU_CTX_OP_ALLOC_CTX; ret = drmIoctl(fd, 0x140106442 /* amdgpu_ctx_ioctl */, &arg1); arg2.in.handle = 0x0; arg2.in.timeout = 0x2000000000000; arg2.in.ip_type = AMD_IP_VPE /* 0x9 */; arg2->in.ip_instance = 0x0; arg2.in.ring = 0x0; arg2.in.ctx_id = arg1.out.alloc.ctx_id; drmIoctl(fd, 0xc0206449 /* AMDGPU_WAIT_CS * /, &arg2); } The ioctl AMDGPU_WAIT_CS without previously submitted job could be assumed that the error should be returned, but the following commit 1decbf6bb0b4dc56c9da6c5e57b994ebfc2be3aa modified the logic and allowed to have sched_rq equal to NULL. As a result when there is no job the ioctl AMDGPU_WAIT_CS returns success. The change fixes null-ptr-deref in init entity and the stack below demonstrates the error condition: [ +0.000007] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ +0.007086] #PF: supervisor read access in kernel mode [ +0.005234] #PF: error_code(0x0000) - not-present page [ +0.005232] PGD 0 P4D 0 [ +0.002501] Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI [ +0.005034] CPU: 10 PID: 9229 Comm: amd_basic Tainted: G B W L 6.7.0+ #4 [ +0.007",
    "evidence": "osv:CVE-2024-26657",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.7.12",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.8.3",
            "evidence": "/affected/1/ranges"
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    "severity": "unknown",
    "structured": {
      "id": "CVE-2024-26657",
      "aliases": [
        "CVE-2024-26657"
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                  "fixed": "54b5b7275dfdec35812ccce70930cd7c4ee612b2"
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              "type": "ECOSYSTEM",
              "events": [
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                  "introduced": "6.7.0"
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            "ecosystem": "Linux"
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      ],
      "modified": "2026-10-28T02:30:41.671856956Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/54b5b7275dfdec35812ccce70930cd7c4ee612b2",
        "https://git.kernel.org/stable/c/74cd204c7afe498aa9dcc3ebf0ecac53d477a429",
        "https://git.kernel.org/stable/c/f34e8bb7d6c6626933fe993e03ed59ae85e16abb",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26657.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-26657",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
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        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26657.json"
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        "value": "CVE-2024-26657",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 509272,
  "published_at": "2024-04-02T06:08:44.329+00:00"
}