{"cve":"CVE-2023-52849","nvd":{"published":"2024-05-21T16:15:22.023","modified":"2026-06-17T06:43:43.730","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/mem: Fix shutdown order\n\nIra reports that removing cxl_mock_mem causes a crash with the following\ntrace:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000044\n [..]\n RIP: 0010:cxl_region_decode_reset+0x7f/0x180 [cxl_core]\n [..]\n Call Trace:\n  <TASK>\n  cxl_region_detach+0xe8/0x210 [cxl_core]\n  cxl_decoder_kill_region+0x27/0x40 [cxl_core]\n  cxld_unregister+0x29/0x40 [cxl_core]\n  devres_release_all+0xb8/0x110\n  device_unbind_cleanup+0xe/0x70\n  device_release_driver_internal+0x1d2/0x210\n  bus_remove_device+0xd7/0x150\n  device_del+0x155/0x3e0\n  device_unregister+0x13/0x60\n  devm_release_action+0x4d/0x90\n  ? __pfx_unregister_port+0x10/0x10 [cxl_core]\n  delete_endpoint+0x121/0x130 [cxl_core]\n  devres_release_all+0xb8/0x110\n  device_unbind_cleanup+0xe/0x70\n  device_release_driver_internal+0x1d2/0x210\n  bus_remove_device+0xd7/0x150\n  device_del+0x155/0x3e0\n  ? lock_release+0x142/0x290\n  cdev_device_del+0x15/0x50\n  cxl_memdev_unregister+0x54/0x70 [cxl_core]\n\nThis crash is due to the clearing out the cxl_memdev's driver context\n(@cxlds) before the subsystem is done with it. This is ultimately due to\nthe region(s), that this memdev is a member, being torn down and expecting\nto be able to de-reference @cxlds, like here:\n\nstatic int cxl_region_decode_reset(struct cxl_region *cxlr, int count)\n...\n                if (cxlds->rcd)\n                        goto endpoint_reset;\n...\n\nFix it by keeping the driver context valid until memdev-device\nunregistration, and subsequently the entire stack of related\ndependencies, unwinds.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/0ca074f7d788627a4e0b047ca5fbdb5fc567220c","https://git.kernel.org/stable/c/20bd0198bebdd706bd4614b3933ef70d7c19618f","https://git.kernel.org/stable/c/7c7371b41a14e86f53e7dbe5baa7b1d3e0ab324b","https://git.kernel.org/stable/c/88d3917f82ed4215a2154432c26de1480a61b209","https://git.kernel.org/stable/c/cad22a757029c3a1985c221a2d4a6491ad4035ae"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2023-52849","score":0.00236,"percentile":0.14581,"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."]}