{"id":"CVE-2023-53445","summary":"net: qrtr: Fix a refcount bug in qrtr_recvmsg()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qrtr: Fix a refcount bug in qrtr_recvmsg()\n\nSyzbot reported a bug as following:\n\nrefcount_t: addition on 0; use-after-free.\n...\nRIP: 0010:refcount_warn_saturate+0x17c/0x1f0 lib/refcount.c:25\n...\nCall Trace:\n \u003cTASK\u003e\n __refcount_add include/linux/refcount.h:199 [inline]\n __refcount_inc include/linux/refcount.h:250 [inline]\n refcount_inc include/linux/refcount.h:267 [inline]\n kref_get include/linux/kref.h:45 [inline]\n qrtr_node_acquire net/qrtr/af_qrtr.c:202 [inline]\n qrtr_node_lookup net/qrtr/af_qrtr.c:398 [inline]\n qrtr_send_resume_tx net/qrtr/af_qrtr.c:1003 [inline]\n qrtr_recvmsg+0x85f/0x990 net/qrtr/af_qrtr.c:1070\n sock_recvmsg_nosec net/socket.c:1017 [inline]\n sock_recvmsg+0xe2/0x160 net/socket.c:1038\n qrtr_ns_worker+0x170/0x1700 net/qrtr/ns.c:688\n process_one_work+0x991/0x15c0 kernel/workqueue.c:2390\n worker_thread+0x669/0x1090 kernel/workqueue.c:2537\n\nIt occurs in the concurrent scenario of qrtr_recvmsg() and\nqrtr_endpoint_unregister() as following:\n\n\tcpu0\t\t\t\t\tcpu1\nqrtr_recvmsg\t\t\t\tqrtr_endpoint_unregister\nqrtr_send_resume_tx\t\t\tqrtr_node_release\nqrtr_node_lookup\t\t\tmutex_lock(&qrtr_node_lock)\nspin_lock_irqsave(&qrtr_nodes_lock, )\trefcount_dec_and_test(&node-\u003eref) [node-\u003eref == 0]\nradix_tree_lookup [node != NULL]\t__qrtr_node_release\nqrtr_node_acquire\t\t\tspin_lock_irqsave(&qrtr_nodes_lock, )\nkref_get(&node-\u003eref) [WARNING]\t\t...\n\t\t\t\t\tmutex_unlock(&qrtr_node_lock)\n\nUse qrtr_node_lock to protect qrtr_node_lookup() implementation, this\nis actually improving the protection of node reference.","modified":"2026-04-02T09:44:14.148346Z","published":"2025-09-18T16:04:21.257Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53445.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/44d807320000db0d0013372ad39b53e12d52f758"},{"type":"WEB","url":"https://git.kernel.org/stable/c/48a07f6e00d305597396da4d7494b81cec05b9d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/98a9cd82c541ef6cbdb829cd6c05cbbb471e373c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aa95efa187b4114075f312b3c4680d050b56fdec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b9ba5906c42089f8e1d0001b7b50a7940f086cbb"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53445.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53445"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0a7e0d0ef05440db03c3199e84d228db943b237f"},{"fixed":"98a9cd82c541ef6cbdb829cd6c05cbbb471e373c"},{"fixed":"b9ba5906c42089f8e1d0001b7b50a7940f086cbb"},{"fixed":"aa95efa187b4114075f312b3c4680d050b56fdec"},{"fixed":"48a07f6e00d305597396da4d7494b81cec05b9d3"},{"fixed":"44d807320000db0d0013372ad39b53e12d52f758"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53445.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}