{"id":"CVE-2026-98850","summary":"net/packet: prevent TX_RING byte count overflow","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: prevent TX_RING byte count overflow\n\ntpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds\neach valid packet length to the signed int len_sum. Userspace can\nrecycle completed frames concurrently, so a single blocking send call\nis not bounded by the ring size.\n\nAfter enough successful transmissions len_sum wraps into the negative\nrange. In particular, 65536 65535-byte frames followed by a 65007-byte\nframe produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats\nthat as an impossible return and triggers a BUG. On systems configured\nto panic on oops, a CAP_NET_RAW holder can panic the host kernel.\n\nStop before the next frame would make the byte count exceed INT_MAX.\nThe positive short count leaves that frame pending for a later send\ncall.\n\nA two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build\nof Linux 7.3-rc4. With this change, the same reproducer returned the\nexpected positive short count without an oops.","modified":"2026-10-19T02:47:35.496593027Z","published":"2026-10-18T15:50:50.062Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98850.json","cna_assigner":"Linux"},"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/2cf81fc9505b148b1b70068303ea6ea4b1212403"},{"type":"WEB","url":"https://git.kernel.org/stable/c/69ca64bbb528898916f309552053c32a04a36ebc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9fd63d284e251332f4874ef9023cde472f315f86"},{"type":"WEB","url":"https://git.kernel.org/stable/c/be12b221c0301111eeb023be04add3c6ad7c21fe"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98850.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98850"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1"},{"fixed":"be12b221c0301111eeb023be04add3c6ad7c21fe"},{"fixed":"69ca64bbb528898916f309552053c32a04a36ebc"},{"fixed":"9fd63d284e251332f4874ef9023cde472f315f86"},{"fixed":"2cf81fc9505b148b1b70068303ea6ea4b1212403"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98850.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.31"},{"fixed":"6.12.113"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.56"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98850.json"}}],"schema_version":"1.9.0"}