{"id":"CVE-2026-89950","summary":"batman-adv: mcast: linearize skbuff for packet generation","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: mcast: linearize skbuff for packet generation\n\nbatadv_mcast_forw_packet() and batadv_mcast_forw_scrape() is not only\ncalled (indirectly) by the unsharing+linearizing batadv_recv_mcast_packet()\nhandler. When it is called (indirectly) by batadv_mcast_forw_mcsend() then\nit will be unshared but not linearized. The SKB_LINEAR_ASSERT() can\ntherefore cause a fatal BUG().\n\nThe linearization should happen during the expansion of the head because\nthe scrape function can be hit already during the initial\nbatadv_mcast_forw_mode() selection code:\n\n* batadv_interface_tx\n* batadv_mcast_forw_mode\n* batadv_mcast_forw_mode_by_count()\n* batadv_mcast_forw_push()\n  -\u003e calls batadv_mcast_forw_expand_head() before everything else\n* batadv_mcast_forw_push_tvlvs()\n* batadv_mcast_forw_push_dests()\n* batadv_mcast_forw_push_adjust_padding()\n* batadv_mcast_forw_scrape()","modified":"2026-09-18T03:48:34.353086267Z","published":"2026-09-16T10:32:35.485Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89950.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2879177539e3ece483a8e5406970373698e9a6c5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6a30a59e2660afd03c975f1b8eae6a2301161197"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a9603e0a7cb5e0cddc6b23af153cf7daafc5c55e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c32e5e25c41201c8c3b796a4ab2c45103187091e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89950.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89950"},{"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":"90039133221e33964ccb4a536dad7eb0a372fff7"},{"fixed":"a9603e0a7cb5e0cddc6b23af153cf7daafc5c55e"},{"fixed":"c32e5e25c41201c8c3b796a4ab2c45103187091e"},{"fixed":"2879177539e3ece483a8e5406970373698e9a6c5"},{"fixed":"6a30a59e2660afd03c975f1b8eae6a2301161197"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89950.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.51"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89950.json"}}],"schema_version":"1.9.0"}