{"id":"CVE-2026-23348","title":"cxl: Fix race of nvdimm_bus object when creating nvdimm objects","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ncxl: Fix race of nvdimm_bus object when creating nvdimm objects\n\nFound issue during running of cxl-translate.sh unit test. Adding a 3s\nsleep right before the test seems…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 5fc4e150c5ada5f7d20d8f9f1b351f10481fbdf7","Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 5b230daeee420833287cc77314439903e5312f10","Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 96a1fd0d84b17360840f344826897fa71049870e","Linux 5.14"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T21:27:33.479828Z"},"published":"2026-03-25","updated":"2026-11-05","sourceUpdated":"2026-11-05T21:33:41.580Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23348","references":[{"url":"https://git.kernel.org/stable/c/5fc4e150c5ada5f7d20d8f9f1b351f10481fbdf7"},{"url":"https://git.kernel.org/stable/c/5b230daeee420833287cc77314439903e5312f10"},{"url":"https://git.kernel.org/stable/c/96a1fd0d84b17360840f344826897fa71049870e"}],"tags":["cve.org"],"epss":0.00091,"epssPercentile":0.00471,"ingestedAt":"2026-11-05T22:38:32.119Z","slug":"CVE-2026-23348","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ncxl: Fix race of nvdimm_bus object when creating nvdimm objects\n\nFound issue during running of cxl-translate.sh unit test. Adding a 3s\nsleep right before the test seems to make the issue reproduce fairly\nconsistently. The cxl_translate module has dependency on cxl_acpi and\ncauses orphaned nvdimm objects to reprobe after cxl_acpi is removed.\nThe nvdimm_bus object is registered by the cxl_nvb object when\ncxl_acpi_probe() is called. With the nvdimm_bus object missing,\n__nd_device_register() will trigger NULL pointer dereference when\naccessing the dev->parent that points to &nvdimm_bus->dev.\n\n[  192.884510] BUG: kernel NULL pointer dereference, address: 000000000000006c\n[  192.895383] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20250812-19.fc42 08/12/2025\n[  192.897721] Workqueue: cxl_port cxl_bus_rescan_queue [cxl_core]\n[  192.899459] RIP: 0010:kobject_get+0xc/0x90\n[  192.924871] Call Trace:\n[  192.925959]  <TASK>\n[  192.926976]  ? pm_runtime_init+0xb9/0xe0\n[  192.929712]  __nd_device_register.part.0+0x4d/0xc0 [libnvdimm]\n[  192.933314]  __nvdimm_create+0x206/0x290 [libnvdimm]\n[  192.936662]  cxl_nvdimm_probe+0x119/0x1d0 [cxl_pmem]\n[  192.940245]  cxl_bus_probe+0x1a/0x60 [cxl_core]\n[  192.943349]  really_probe+0xde/0x380\n\nThis patch also relies on the previous change where\ndevm_cxl_add_nvdimm_bridge() is called from drivers/cxl/pmem.c instead\nof drivers/cxl/core.c to ensure the dependency of cxl_acpi on cxl_pmem.\n\n1. Set probe_type of cxl_nvb to PROBE_FORCE_SYNCHRONOUS to ensure the\n   driver is probed synchronously when add_device() is called.\n2. Add a check in __devm_cxl_add_nvdimm_bridge() to ensure that the\n   cxl_nvb driver is attached during cxl_acpi_probe().\n3. Take the cxl_root uport_dev lock and the cxl_nvb->dev lock in\n   devm_cxl_add_nvdimm() before checking nvdimm_bus is valid.\n4. Set cxl_nvdimm flag to CXL_NVD_F_INVALIDATED so cxl_nvdimm_probe()\n   will exit with -EBUSY.\n\nThe removal of cxl_nvdimm devices should prevent any orphaned devices\nfrom probing once the nvdimm_bus is gone.\n\n[ dj: Fixed 0-day reported kdoc issue. ]\n[ dj: Fix cxl_nvb reference leak on error. Gregory (kreview-0811365) ]\n\n## Affected\n\n- `Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 5fc4e150c5ada5f7d20d8f9f1b351f10481fbdf7`\n- `Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 5b230daeee420833287cc77314439903e5312f10`\n- `Linux >= 8fdcb1704f61a8fd9be0f3849a174d084def0666 < 96a1fd0d84b17360840f344826897fa71049870e`\n- `Linux 5.14`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}