{"cve":"CVE-2024-56568","nvd":{"published":"2024-12-27T15:15:15.733","modified":"2026-06-17T08:12:26.023","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\niommu/arm-smmu: Defer probe of clients after smmu device bound\n\nNull pointer dereference occurs due to a race between smmu\ndriver probe and client driver probe, when of_dma_configure()\nfor client is called after the iommu_device_register() for smmu driver\nprobe has executed but before the driver_bound() for smmu driver\nhas been called.\n\nFollowing is how the race occurs:\n\nT1:Smmu device probe\t\tT2: Client device probe\n\nreally_probe()\narm_smmu_device_probe()\niommu_device_register()\n\t\t\t\t\treally_probe()\n\t\t\t\t\tplatform_dma_configure()\n\t\t\t\t\tof_dma_configure()\n\t\t\t\t\tof_dma_configure_id()\n\t\t\t\t\tof_iommu_configure()\n\t\t\t\t\tiommu_probe_device()\n\t\t\t\t\tiommu_init_device()\n\t\t\t\t\tarm_smmu_probe_device()\n\t\t\t\t\tarm_smmu_get_by_fwnode()\n\t\t\t\t\t\tdriver_find_device_by_fwnode()\n\t\t\t\t\t\tdriver_find_device()\n\t\t\t\t\t\tnext_device()\n\t\t\t\t\t\tklist_next()\n\t\t\t\t\t\t    /* null ptr\n\t\t\t\t\t\t       assigned to smmu */\n\t\t\t\t\t/* null ptr dereference\n\t\t\t\t\t   while smmu->streamid_mask */\ndriver_bound()\n\tklist_add_tail()\n\nWhen this null smmu pointer is dereferenced later in\narm_smmu_probe_device, the device crashes.\n\nFix this by deferring the probe of the client device\nuntil the smmu device has bound to the arm smmu driver.\n\n[will: Add comment]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":["CWE-362","CWE-476"],"references":["https://git.kernel.org/stable/c/229e6ee43d2a160a1592b83aad620d6027084aad","https://git.kernel.org/stable/c/4a9485918a042e3114890dfbe19839a1897f8b2c","https://git.kernel.org/stable/c/5018696b19bc6c021e934a8a59f4b1dd8c0ac9f8","https://git.kernel.org/stable/c/c2527d07c7e9cda2c6165d5edccf74752baac1b0","https://git.kernel.org/stable/c/dc02407ea952e20c544a078a6be2e6f008327973"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:57:56.913276502+00:00"},"epss":{"cve":"CVE-2024-56568","score":0.00164,"percentile":0.05549,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}