{"id":"CVE-2025-37772","summary":"RDMA/cma: Fix workqueue crash in cma_netevent_work_handler","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/cma: Fix workqueue crash in cma_netevent_work_handler\n\nstruct rdma_cm_id has member \"struct work_struct net_work\"\nthat is reused for enqueuing cma_netevent_work_handler()s\nonto cma_wq.\n\nBelow crash[1] can occur if more than one call to\ncma_netevent_callback() occurs in quick succession,\nwhich further enqueues cma_netevent_work_handler()s for the\nsame rdma_cm_id, overwriting any previously queued work-item(s)\nthat was just scheduled to run i.e. there is no guarantee\nthe queued work item may run between two successive calls\nto cma_netevent_callback() and the 2nd INIT_WORK would overwrite\nthe 1st work item (for the same rdma_cm_id), despite grabbing\nid_table_lock during enqueue.\n\nAlso drgn analysis [2] indicates the work item was likely overwritten.\n\nFix this by moving the INIT_WORK() to __rdma_create_id(),\nso that it doesn't race with any existing queue_work() or\nits worker thread.\n\n[1] Trimmed crash stack:\n=============================================\nBUG: kernel NULL pointer dereference, address: 0000000000000008\nkworker/u256:6 ... 6.12.0-0...\nWorkqueue:  cma_netevent_work_handler [rdma_cm] (rdma_cm)\nRIP: 0010:process_one_work+0xba/0x31a\nCall Trace:\n worker_thread+0x266/0x3a0\n kthread+0xcf/0x100\n ret_from_fork+0x31/0x50\n ret_from_fork_asm+0x1a/0x30\n=============================================\n\n[2] drgn crash analysis:\n\n\u003e\u003e\u003e trace = prog.crashed_thread().stack_trace()\n\u003e\u003e\u003e trace\n(0)  crash_setup_regs (./arch/x86/include/asm/kexec.h:111:15)\n(1)  __crash_kexec (kernel/crash_core.c:122:4)\n(2)  panic (kernel/panic.c:399:3)\n(3)  oops_end (arch/x86/kernel/dumpstack.c:382:3)\n...\n(8)  process_one_work (kernel/workqueue.c:3168:2)\n(9)  process_scheduled_works (kernel/workqueue.c:3310:3)\n(10) worker_thread (kernel/workqueue.c:3391:4)\n(11) kthread (kernel/kthread.c:389:9)\n\nLine workqueue.c:3168 for this kernel version is in process_one_work():\n3168\tstrscpy(worker-\u003edesc, pwq-\u003ewq-\u003ename, WORKER_DESC_LEN);\n\n\u003e\u003e\u003e trace[8][\"work\"]\n*(struct work_struct *)0xffff92577d0a21d8 = {\n\t.data = (atomic_long_t){\n\t\t.counter = (s64)536870912,    \u003c=== Note\n\t},\n\t.entry = (struct list_head){\n\t\t.next = (struct list_head *)0xffff924d075924c0,\n\t\t.prev = (struct list_head *)0xffff924d075924c0,\n\t},\n\t.func = (work_func_t)cma_netevent_work_handler+0x0 = 0xffffffffc2cec280,\n}\n\nSuspicion is that pwq is NULL:\n\u003e\u003e\u003e trace[8][\"pwq\"]\n(struct pool_workqueue *)\u003cabsent\u003e\n\nIn process_one_work(), pwq is assigned from:\nstruct pool_workqueue *pwq = get_work_pwq(work);\n\nand get_work_pwq() is:\nstatic struct pool_workqueue *get_work_pwq(struct work_struct *work)\n{\n \tunsigned long data = atomic_long_read(&work-\u003edata);\n\n \tif (data & WORK_STRUCT_PWQ)\n \t\treturn work_struct_pwq(data);\n \telse\n \t\treturn NULL;\n}\n\nWORK_STRUCT_PWQ is 0x4:\n\u003e\u003e\u003e print(repr(prog['WORK_STRUCT_PWQ']))\nObject(prog, 'enum work_flags', value=4)\n\nBut work-\u003edata is 536870912 which is 0x20000000.\nSo, get_work_pwq() returns NULL and we crash in process_one_work():\n3168\tstrscpy(worker-\u003edesc, pwq-\u003ewq-\u003ename, WORKER_DESC_LEN);\n=============================================","modified":"2026-04-02T12:47:25.166549Z","published":"2025-05-01T13:07:12.168Z","related":["SUSE-SU-2025:01964-1","SUSE-SU-2025:01965-1","SUSE-SU-2025:02000-1","SUSE-SU-2025:02254-1","SUSE-SU-2025:02307-1","SUSE-SU-2025:02333-1","SUSE-SU-2025:02923-1","SUSE-SU-2025:20408-1","SUSE-SU-2025:20413-1","SUSE-SU-2025:20419-1","SUSE-SU-2025:20421-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37772.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/45f5dcdd049719fb999393b30679605f16ebce14"},{"type":"WEB","url":"https://git.kernel.org/stable/c/51003b2c872c63d28bcf5fbcc52cf7b05615f7b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b172a4a0de254f1fcce7591833a9a63547c2f447"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c2b169fc7a12665d8a675c1ff14bca1b9c63fb9a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d23fd7a539ac078df119707110686a5b226ee3bb"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37772.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-37772"},{"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":"925d046e7e52c71c3531199ce137e141807ef740"},{"fixed":"51003b2c872c63d28bcf5fbcc52cf7b05615f7b7"},{"fixed":"c2b169fc7a12665d8a675c1ff14bca1b9c63fb9a"},{"fixed":"d23fd7a539ac078df119707110686a5b226ee3bb"},{"fixed":"b172a4a0de254f1fcce7591833a9a63547c2f447"},{"fixed":"45f5dcdd049719fb999393b30679605f16ebce14"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-37772.json"}}],"schema_version":"1.7.5"}