---
id: CVE-2022-49198
title: 'mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb

  Got crash when doing pressure test of mptcp:

  ===========================================…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 289f2f58266777f45a52cd55dea96d736e6244c9 <
    af61a8f7603926c26158153d0a0755764d82657c
  - >-
    Linux >= f70cad1085d1e01d3ec73c1078405f906237feee <
    752add6f5ce5305e55d8bda4ac8d69be3a09f14d
  - >-
    Linux >= f70cad1085d1e01d3ec73c1078405f906237feee <
    4d54181eba4b077fb74033a7186898ad4000a7a5
  - >-
    Linux >= f70cad1085d1e01d3ec73c1078405f906237feee <
    3ef3905aa3b5b3e222ee6eb0210bfd999417a8cc
  - Linux 5.16
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T19:44:27.626509Z'
published: '2025-02-26'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T19:49:37.133Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-49198'
references:
  - url: 'https://git.kernel.org/stable/c/af61a8f7603926c26158153d0a0755764d82657c'
  - url: 'https://git.kernel.org/stable/c/752add6f5ce5305e55d8bda4ac8d69be3a09f14d'
  - url: 'https://git.kernel.org/stable/c/4d54181eba4b077fb74033a7186898ad4000a7a5'
  - url: 'https://git.kernel.org/stable/c/3ef3905aa3b5b3e222ee6eb0210bfd999417a8cc'
tags:
  - cve.org
epss: 0.00261
epssPercentile: 0.17961
ingestedAt: '2026-11-05T22:38:31.565Z'
---

## Overview

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

mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb

Got crash when doing pressure test of mptcp:

===========================================================================
dst_release: dst:ffffa06ce6e5c058 refcnt:-1
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffffa06ce6e5c058
PGD 190a01067 P4D 190a01067 PUD 43fffb067 PMD 22e403063 PTE 8000000226e5c063
Oops: 0011 [#1] SMP PTI
CPU: 7 PID: 7823 Comm: kworker/7:0 Kdump: loaded Tainted: G            E
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.2.1 04/01/2014
Call Trace:
 ? skb_release_head_state+0x68/0x100
 ? skb_release_all+0xe/0x30
 ? kfree_skb+0x32/0xa0
 ? mptcp_sendmsg_frag+0x57e/0x750
 ? __mptcp_retrans+0x21b/0x3c0
 ? __switch_to_asm+0x35/0x70
 ? mptcp_worker+0x25e/0x320
 ? process_one_work+0x1a7/0x360
 ? worker_thread+0x30/0x390
 ? create_worker+0x1a0/0x1a0
 ? kthread+0x112/0x130
 ? kthread_flush_work_fn+0x10/0x10
 ? ret_from_fork+0x35/0x40
===========================================================================

In __mptcp_alloc_tx_skb skb was allocated and skb->tcp_tsorted_anchor will
be initialized, in under memory pressure situation sk_wmem_schedule will
return false and then kfree_skb. In this case skb->_skb_refdst is not null
because_skb_refdst and tcp_tsorted_anchor are stored in the same mem, and
kfree_skb will try to release dst and cause crash.

## Affected

- `Linux >= 289f2f58266777f45a52cd55dea96d736e6244c9 < af61a8f7603926c26158153d0a0755764d82657c`
- `Linux >= f70cad1085d1e01d3ec73c1078405f906237feee < 752add6f5ce5305e55d8bda4ac8d69be3a09f14d`
- `Linux >= f70cad1085d1e01d3ec73c1078405f906237feee < 4d54181eba4b077fb74033a7186898ad4000a7a5`
- `Linux >= f70cad1085d1e01d3ec73c1078405f906237feee < 3ef3905aa3b5b3e222ee6eb0210bfd999417a8cc`
- `Linux 5.16`

## Remediation

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