{"id":"CVE-2026-98787","summary":"bpf: Fix missing migration protection in __rhtab_map_lookup_and_delete_batch()","details":"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.","modified":"2026-10-20T02:30:14.845810911Z","published":"2026-10-18T15:48:23.947Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98787.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/94f41ec5fa578765b74ad5736c2f029e7aabc46d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/de020dc8049bfb2b22e3b6d99c031feb2e22d112"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98787.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98787"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"818e0084822742fc00eacbf5df3476a5e72c7d0e"},{"fixed":"94f41ec5fa578765b74ad5736c2f029e7aabc46d"},{"fixed":"de020dc8049bfb2b22e3b6d99c031feb2e22d112"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98787.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98787.json"}}],"schema_version":"1.9.0"}