{"id":"CVE-2026-98787","published":"2026-10-18T16:17:32.690","lastModified":"2026-10-19T10:19:42.783","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix missing migration protection in __rhtab_map_lookup_and_delete_batch()\n\nbpf_mem_cache_free_rcu() uses this_cpu_ptr() which requires migration\nto be disabled. All callers of rhtab_delete_elem() disable migration\nexcept __rhtab_map_lookup_and_delete_batch(), which calls it under\nrcu_read_lock() only.\n\nOn CONFIG_PREEMPT_RCU, rcu_read_lock() does not disable preemption or\nmigration, so the task can migrate between CPUs during the delete loop,\ncausing this_cpu_ptr() to trigger:\n\n  BUG: using smp_processor_id() in preemptible [00000000] code\n\nFix by wrapping the delete loop in migrate_disable()/migrate_enable()\nin __rhtab_map_lookup_and_delete_batch(), matching the migration\nprotection that the other callers already provide.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/94f41ec5fa578765b74ad5736c2f029e7aabc46d","tags":[]},{"url":"https://git.kernel.org/stable/c/de020dc8049bfb2b22e3b6d99c031feb2e22d112","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}