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GHSA-52WF-QX53-M2M5

Vulnerability from github – Published: 2025-05-01 15:31 – Updated: 2025-11-07 21:31
VLAI
Details

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

tcp: cdg: allow tcp_cdg_release() to be called multiple times

Apparently, mptcp is able to call tcp_disconnect() on an already disconnected flow. This is generally fine, unless current congestion control is CDG, because it might trigger a double-free [1]

Instead of fixing MPTCP, and future bugs, we can make tcp_disconnect() more resilient.

[1] BUG: KASAN: double-free in slab_free mm/slub.c:3539 [inline] BUG: KASAN: double-free in kfree+0xe2/0x580 mm/slub.c:4567

CPU: 0 PID: 3645 Comm: kworker/0:7 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: events mptcp_worker Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report_invalid_free+0x81/0x190 mm/kasan/report.c:462 _kasanslab_free+0x18b/0x1c0 mm/kasan/common.c:356 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 tcp_disconnect+0x980/0x1e20 net/ipv4/tcp.c:3145 mptcp_close_ssk+0x5ca/0x7e0 net/mptcp/protocol.c:2327 mptcp_do_fastclose net/mptcp/protocol.c:2592 [inline] mptcp_worker+0x78c/0xff0 net/mptcp/protocol.c:2627 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

Allocated by task 3671: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] _kasankmalloc mm/kasan/common.c:516 [inline] __kasan_kmalloc mm/kasan/common.c:475 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525 kmalloc_array include/linux/slab.h:640 [inline] kcalloc include/linux/slab.h:671 [inline] tcp_cdg_init+0x10d/0x170 net/ipv4/tcp_cdg.c:380 tcp_init_congestion_control+0xab/0x550 net/ipv4/tcp_cong.c:193 tcp_reinit_congestion_control net/ipv4/tcp_cong.c:217 [inline] tcp_set_congestion_control+0x96c/0xaa0 net/ipv4/tcp_cong.c:391 do_tcp_setsockopt+0x505/0x2320 net/ipv4/tcp.c:3513 tcp_setsockopt+0xd4/0x100 net/ipv4/tcp.c:3801 mptcp_setsockopt+0x35f/0x2570 net/mptcp/sockopt.c:844 __sys_setsockopt+0x2d6/0x690 net/socket.c:2252 __do_sys_setsockopt net/socket.c:2263 [inline] __se_sys_setsockopt net/socket.c:2260 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 16: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 _kasanslab_free mm/kasan/common.c:367 [inline] __kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 tcp_cleanup_congestion_control+0x70/0x120 net/ipv4/tcp_cong.c:226 tcp_v4_destroy_sock+0xdd/0x750 net/ipv4/tcp_ipv4.c:2254 tcp_v6_destroy_sock+0x11/0x20 net/ipv6/tcp_ipv6.c:1969 inet_csk_destroy_sock+0x196/0x440 net/ipv4/inet_connection_sock.c:1157 tcp_done+0x23b/0x340 net/ipv4/tcp.c:4649 tcp_rcv_state_process+0x40e7/0x4990 net/ipv4/tcp_input.c:6624 tcp_v6_do_rcv+0x3fc/0x13c0 net/ipv6/tcp_ipv6.c:1525 tcp_v6_rcv+0x2e8e/0x3830 net/ipv6/tcp_ipv6.c:1759 ip6_protocol_deliver_rcu+0x2db/0x1950 net/ipv6/ip6_input.c:439 ip6_input_finish+0x14c/0x2c0 net/ipv6/ip6_input.c:484 NF_HOOK include/linux/netfilter.h:302 [inline] NF_HOOK include/linux/netfilter.h:296 [inline] ip6_input+0x9c/0xd ---truncated---

Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2022-49775"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-415"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-01T15:16:00Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: cdg: allow tcp_cdg_release() to be called multiple times\n\nApparently, mptcp is able to call tcp_disconnect() on an already\ndisconnected flow. This is generally fine, unless current congestion\ncontrol is CDG, because it might trigger a double-free [1]\n\nInstead of fixing MPTCP, and future bugs, we can make tcp_disconnect()\nmore resilient.\n\n[1]\nBUG: KASAN: double-free in slab_free mm/slub.c:3539 [inline]\nBUG: KASAN: double-free in kfree+0xe2/0x580 mm/slub.c:4567\n\nCPU: 0 PID: 3645 Comm: kworker/0:7 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022\nWorkqueue: events mptcp_worker\nCall Trace:\n\u003cTASK\u003e\n__dump_stack lib/dump_stack.c:88 [inline]\ndump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\nprint_address_description mm/kasan/report.c:317 [inline]\nprint_report.cold+0x2ba/0x719 mm/kasan/report.c:433\nkasan_report_invalid_free+0x81/0x190 mm/kasan/report.c:462\n____kasan_slab_free+0x18b/0x1c0 mm/kasan/common.c:356\nkasan_slab_free include/linux/kasan.h:200 [inline]\nslab_free_hook mm/slub.c:1759 [inline]\nslab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785\nslab_free mm/slub.c:3539 [inline]\nkfree+0xe2/0x580 mm/slub.c:4567\ntcp_disconnect+0x980/0x1e20 net/ipv4/tcp.c:3145\n__mptcp_close_ssk+0x5ca/0x7e0 net/mptcp/protocol.c:2327\nmptcp_do_fastclose net/mptcp/protocol.c:2592 [inline]\nmptcp_worker+0x78c/0xff0 net/mptcp/protocol.c:2627\nprocess_one_work+0x991/0x1610 kernel/workqueue.c:2289\nworker_thread+0x665/0x1080 kernel/workqueue.c:2436\nkthread+0x2e4/0x3a0 kernel/kthread.c:376\nret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306\n\u003c/TASK\u003e\n\nAllocated by task 3671:\nkasan_save_stack+0x1e/0x40 mm/kasan/common.c:38\nkasan_set_track mm/kasan/common.c:45 [inline]\nset_alloc_info mm/kasan/common.c:437 [inline]\n____kasan_kmalloc mm/kasan/common.c:516 [inline]\n____kasan_kmalloc mm/kasan/common.c:475 [inline]\n__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525\nkmalloc_array include/linux/slab.h:640 [inline]\nkcalloc include/linux/slab.h:671 [inline]\ntcp_cdg_init+0x10d/0x170 net/ipv4/tcp_cdg.c:380\ntcp_init_congestion_control+0xab/0x550 net/ipv4/tcp_cong.c:193\ntcp_reinit_congestion_control net/ipv4/tcp_cong.c:217 [inline]\ntcp_set_congestion_control+0x96c/0xaa0 net/ipv4/tcp_cong.c:391\ndo_tcp_setsockopt+0x505/0x2320 net/ipv4/tcp.c:3513\ntcp_setsockopt+0xd4/0x100 net/ipv4/tcp.c:3801\nmptcp_setsockopt+0x35f/0x2570 net/mptcp/sockopt.c:844\n__sys_setsockopt+0x2d6/0x690 net/socket.c:2252\n__do_sys_setsockopt net/socket.c:2263 [inline]\n__se_sys_setsockopt net/socket.c:2260 [inline]\n__x64_sys_setsockopt+0xba/0x150 net/socket.c:2260\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nFreed by task 16:\nkasan_save_stack+0x1e/0x40 mm/kasan/common.c:38\nkasan_set_track+0x21/0x30 mm/kasan/common.c:45\nkasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370\n____kasan_slab_free mm/kasan/common.c:367 [inline]\n____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329\nkasan_slab_free include/linux/kasan.h:200 [inline]\nslab_free_hook mm/slub.c:1759 [inline]\nslab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785\nslab_free mm/slub.c:3539 [inline]\nkfree+0xe2/0x580 mm/slub.c:4567\ntcp_cleanup_congestion_control+0x70/0x120 net/ipv4/tcp_cong.c:226\ntcp_v4_destroy_sock+0xdd/0x750 net/ipv4/tcp_ipv4.c:2254\ntcp_v6_destroy_sock+0x11/0x20 net/ipv6/tcp_ipv6.c:1969\ninet_csk_destroy_sock+0x196/0x440 net/ipv4/inet_connection_sock.c:1157\ntcp_done+0x23b/0x340 net/ipv4/tcp.c:4649\ntcp_rcv_state_process+0x40e7/0x4990 net/ipv4/tcp_input.c:6624\ntcp_v6_do_rcv+0x3fc/0x13c0 net/ipv6/tcp_ipv6.c:1525\ntcp_v6_rcv+0x2e8e/0x3830 net/ipv6/tcp_ipv6.c:1759\nip6_protocol_deliver_rcu+0x2db/0x1950 net/ipv6/ip6_input.c:439\nip6_input_finish+0x14c/0x2c0 net/ipv6/ip6_input.c:484\nNF_HOOK include/linux/netfilter.h:302 [inline]\nNF_HOOK include/linux/netfilter.h:296 [inline]\nip6_input+0x9c/0xd\n---truncated---",
  "id": "GHSA-52wf-qx53-m2m5",
  "modified": "2025-11-07T21:31:15Z",
  "published": "2025-05-01T15:31:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-49775"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b19171439016a8e4c97eafe543670ac86e2b8fe"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1b639be27cbf428a5ca01dcf8b5d654194c956f8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/35309be06b6feded2ab2cafbc2bca8534c2fa41e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4026033907cc6186d86b48daa4a252c860db2536"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/72e560cb8c6f80fc2b4afc5d3634a32465e13a51"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/78be2ee0112409ae4e9ee9e326151e0559b3d239"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9e481d87349d2282f400ee1d010a169c99f766b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b49026d9c86f35a4c5bfb8d7345c9c4379828c6b"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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