{"id":"AZL-110995","summary":"CVE-2026-98925 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Fix self-redirect copied_seq double-counting\n\nWhen a BPF stream_verdict program redirects an skb back to the same\nsocket (self-redirect with BPF_F_INGRESS), sk_psock_verdict_apply()\ncalls tcp_eat_skb() which advances tcp_sk-\u003ecopied_seq. However, the\nskb is then delivered to the socket's psock ingress queue and later\nread by tcp_bpf_recvmsg_parser(), which also advances copied_seq via\nthe copied_from_self accounting path. This double-counting causes\ncopied_seq to advance by 2x the actual data length, triggering:\n\n  TCP recvmsg seq # bug 2: copied BF2E806, seq BF2E7FD, \\\n\t\t\t   rcvnxt BF2E806, fl 0\n  WARNING: net/ipv4/tcp.c:2745 at tcp_recvmsg_locked+0x72b/0x2640\n  Call Trace:\n   tcp_recvmsg+0x10a/0x500\n   sock_recvmsg+0x168/0x1d0\n   __sys_recvfrom+0x19a/0x2a0\n   __x64_sys_recvfrom+0xe4/0x1f0\n   do_syscall_64+0xf7/0x530\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n  cleanup rbuf bug: copied BF2E806 seq BF2E806 rcvnxt BF2E806\n  WARNING: net/ipv4/tcp.c:1609 at tcp_cleanup_rbuf+0xf2/0x1c0\n  Call Trace:\n   tcp_recvmsg_locked+0x8d1/0x2640\n   tcp_recvmsg+0x10a/0x500\n   sock_recvmsg+0x168/0x1d0\n   __sys_recvfrom+0x19a/0x2a0\n   __x64_sys_recvfrom+0xe4/0x1f0\n   do_syscall_64+0xf7/0x530\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFix this by converting self-redirect verdict to __SK_PASS at the\nbeginning of sk_psock_verdict_apply(). This bypasses the\n__SK_REDIRECT case entirely (which calls sk_psock_eat_skb), letting\nthe __SK_PASS path queue the skb to the psock ingress queue. The\ndata is then read via tcp_bpf_recvmsg_parser(), which advances\ncopied_seq exactly once through copied_from_self. Cross-socket\nredirects continue through __SK_REDIRECT with sk_psock_eat_skb()\nunchanged.","modified":"2026-10-30T05:35:37Z","published":"2026-10-23T13:17:13Z","upstream":["CVE-2026-98925"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98925"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-110995.json"}}],"schema_version":"1.9.2"}