Paper/Archive/CVE-2026-64025

CVE-2026-64025

Linux Linux — bpf, skmsg: fix verdict sk_data_ready racing with ktls rx

Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: bpf, skmsg: fix verdict sk_data_ready racing with ktls rx sk_psock_strp_data_ready() already checks tls_sw_has_ctx_rx() and defers to psock->saved_data_ready when a TLS RX context is present, avoiding a conflict with the TLS strparser's ownership of the receive queue (commit e91de6afa81c, "bpf: Fix running sk_skb program types with ktls"). sk_psock_verdict_data_ready() has no equivalent guard. When a socket is inserted into a sockmap (BPF_SK_SKB_VERDICT) before TLS RX is configured, tls_sw_strparser_arm() saves sk_psock_verdict_data_ready as rx_ctx->saved_data_ready. On data arrival: tls_data_ready -> tls_strp_data_ready -> tls_rx_msg_ready -> saved_data_ready() = sk_psock_verdict_data_ready() -> tcp_read_skb() drains sk_receive_queue via __skb_unlink() without calling tcp_eat_skb(), so copied_seq is not advanced. tls_strp_msg_load() then finds tcp_inq() >= full_len (stale), calls tcp_recv_skb() on the now-empty queue, hits WARN_ON_ONCE(!first), and returns with rx_ctx->strp.anchor.frag_list pointing at a psock-owned (potentially freed) skb. tls_decrypt_sg() subsequently walks that frag_list: use-after-free. Apply the same fix as sk_psock_strp_data_ready(): if a TLS RX context is present, call psock->saved_data_ready (sock_def_readable) to wake recv() waiters and return immediately, leaving the receive queue untouched. TLS retains sole ownership of the queue and decrypts the record normally through tls_sw_recvmsg().

Affected

ProductAffectedFixed inSource
Linuxef5659280eb13e8ac31c296f58cfdfa1684ac06b – < c9ea01768903ae47f210cd457af1dead6de7a9c3c9ea01768903ae47f210cd457af1dead6de7a9c3CNA
Linuxef5659280eb13e8ac31c296f58cfdfa1684ac06b – < 7c8cf21bc4efb4af18d6096db3f8bd06d622251c7c8cf21bc4efb4af18d6096db3f8bd06d622251cCNA
Linuxef5659280eb13e8ac31c296f58cfdfa1684ac06b – < 1861d369efd62d67796563bf3e01fc22e5626f8b1861d369efd62d67796563bf3e01fc22e5626f8bCNA
Linuxef5659280eb13e8ac31c296f58cfdfa1684ac06b – < 8a52139560f833c3975032e1f5762611e3a36d718a52139560f833c3975032e1f5762611e3a36d71CNA
Linuxef5659280eb13e8ac31c296f58cfdfa1684ac06b – < ddf8029623a1af20e984c040e89ff918158397abddf8029623a1af20e984c040e89ff918158397abCNA
Linux5.10–CNA

Scores by source

Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgit.kernel.org/stable/c/c9ea01768903ae47f210cd457af1dead6de7a9c3refgit.kernel.org/stable/c/7c8cf21bc4efb4af18d6096db3f8bd06d622251crefgit.kernel.org/stable/c/1861d369efd62d67796563bf3e01fc22e5626f8brefgit.kernel.org/stable/c/8a52139560f833c3975032e1f5762611e3a36d71refgit.kernel.org/stable/c/ddf8029623a1af20e984c040e89ff918158397ab