---
id: CVE-2026-98925
title: 'bpf, sockmap: Fix self-redirect copied_seq double-counting'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf, sockmap: Fix self-redirect copied_seq double-counting

  When a BPF stream_verdict program redirects an skb back to the same
  socket (self-redirect with BPF_F_INGRESS…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= fe735073a50eaa71aceb2e990827fe26f33cddd6 <
    cf9aefb26a071cb8b6fdd761c27e022a1184946d
  - >-
    Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa <
    dc98def81e3c629e25fcdd5753b1db93aab27ce9
  - >-
    Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa <
    ef6f2182fee6b9721c005ccfc6aec0a47f79bbfa
  - >-
    Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa <
    ae1ffd04e98beefbe5d83335d506b0bcd5c2a6b3
  - >-
    Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa <
    88942054191185c6f8bea5568cbb5614d1e99af9
  - >-
    Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa <
    490a83d6386eec1d29f470c8d7331677fb46c3b7
  - Linux f9b4a0b537be7a6e5f002ca64b09dcca9c14e6ed
  - Linux >= 6.1.32 < 6.1.189
  - Linux >= 6.3.6 < 6.4
  - Linux 6.4
published: '2026-10-23'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T12:05:53.207Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-98925'
references:
  - url: 'https://git.kernel.org/stable/c/cf9aefb26a071cb8b6fdd761c27e022a1184946d'
  - url: 'https://git.kernel.org/stable/c/dc98def81e3c629e25fcdd5753b1db93aab27ce9'
  - url: 'https://git.kernel.org/stable/c/ef6f2182fee6b9721c005ccfc6aec0a47f79bbfa'
  - url: 'https://git.kernel.org/stable/c/ae1ffd04e98beefbe5d83335d506b0bcd5c2a6b3'
  - url: 'https://git.kernel.org/stable/c/88942054191185c6f8bea5568cbb5614d1e99af9'
  - url: 'https://git.kernel.org/stable/c/490a83d6386eec1d29f470c8d7331677fb46c3b7'
tags:
  - cve.org
ingestedAt: '2026-10-23T13:24:55.567Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

bpf, sockmap: Fix self-redirect copied_seq double-counting

When a BPF stream_verdict program redirects an skb back to the same
socket (self-redirect with BPF_F_INGRESS), sk_psock_verdict_apply()
calls tcp_eat_skb() which advances tcp_sk->copied_seq. However, the
skb is then delivered to the socket's psock ingress queue and later
read by tcp_bpf_recvmsg_parser(), which also advances copied_seq via
the copied_from_self accounting path. This double-counting causes
copied_seq to advance by 2x the actual data length, triggering:

  TCP recvmsg seq # bug 2: copied BF2E806, seq BF2E7FD, \
			   rcvnxt BF2E806, fl 0
  WARNING: net/ipv4/tcp.c:2745 at tcp_recvmsg_locked+0x72b/0x2640
  Call Trace:
   tcp_recvmsg+0x10a/0x500
   sock_recvmsg+0x168/0x1d0
   __sys_recvfrom+0x19a/0x2a0
   __x64_sys_recvfrom+0xe4/0x1f0
   do_syscall_64+0xf7/0x530
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

  cleanup rbuf bug: copied BF2E806 seq BF2E806 rcvnxt BF2E806
  WARNING: net/ipv4/tcp.c:1609 at tcp_cleanup_rbuf+0xf2/0x1c0
  Call Trace:
   tcp_recvmsg_locked+0x8d1/0x2640
   tcp_recvmsg+0x10a/0x500
   sock_recvmsg+0x168/0x1d0
   __sys_recvfrom+0x19a/0x2a0
   __x64_sys_recvfrom+0xe4/0x1f0
   do_syscall_64+0xf7/0x530
   entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fix this by converting self-redirect verdict to __SK_PASS at the
beginning of sk_psock_verdict_apply(). This bypasses the
__SK_REDIRECT case entirely (which calls sk_psock_eat_skb), letting
the __SK_PASS path queue the skb to the psock ingress queue. The
data is then read via tcp_bpf_recvmsg_parser(), which advances
copied_seq exactly once through copied_from_self. Cross-socket
redirects continue through __SK_REDIRECT with sk_psock_eat_skb()
unchanged.

## Affected

- `Linux >= fe735073a50eaa71aceb2e990827fe26f33cddd6 < cf9aefb26a071cb8b6fdd761c27e022a1184946d`
- `Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa < dc98def81e3c629e25fcdd5753b1db93aab27ce9`
- `Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa < ef6f2182fee6b9721c005ccfc6aec0a47f79bbfa`
- `Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa < ae1ffd04e98beefbe5d83335d506b0bcd5c2a6b3`
- `Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa < 88942054191185c6f8bea5568cbb5614d1e99af9`
- `Linux >= e5c6de5fa025882babf89cecbed80acf49b987fa < 490a83d6386eec1d29f470c8d7331677fb46c3b7`
- `Linux f9b4a0b537be7a6e5f002ca64b09dcca9c14e6ed`
- `Linux >= 6.1.32 < 6.1.189`
- `Linux >= 6.3.6 < 6.4`
- `Linux 6.4`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.