fkie_cve-2022-50555
Vulnerability from fkie_nvd
Published
2025-10-07 16:15
Modified
2025-10-08 19:38
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: tipc: fix a null-ptr-deref in tipc_topsrv_accept syzbot found a crash in tipc_topsrv_accept: KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] Workqueue: tipc_rcv tipc_topsrv_accept RIP: 0010:kernel_accept+0x22d/0x350 net/socket.c:3487 Call Trace: <TASK> tipc_topsrv_accept+0x197/0x280 net/tipc/topsrv.c:460 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 It was caused by srv->listener that might be set to null by tipc_topsrv_stop() in net .exit whereas it's still used in tipc_topsrv_accept() worker. srv->listener is protected by srv->idr_lock in tipc_topsrv_stop(), so add a check for srv->listener under srv->idr_lock in tipc_topsrv_accept() to avoid the null-ptr-deref. To ensure the lsock is not released during the tipc_topsrv_accept(), move sock_release() after tipc_topsrv_work_stop() where it's waiting until the tipc_topsrv_accept worker to be done. Note that sk_callback_lock is used to protect sk->sk_user_data instead of srv->listener, and it should check srv in tipc_topsrv_listener_data_ready() instead. This also ensures that no more tipc_topsrv_accept worker will be started after tipc_conn_close() is called in tipc_topsrv_stop() where it sets sk->sk_user_data to null.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/24b129aed8730e48f47d852d58d76825ab6f407c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/32a3d4660b34ce49ac0162338ebe362098e2f5df
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7a939503fc32bff4ed60800b73ff7fbb4aea2142
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/82cb4e4612c633a9ce320e1773114875604a3cce
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ce69bdac2310152bb70845024d5d704c52aabfc3
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/cedb41664e27b2cae7e21487f1bee22dcd84037d
Impacted products
Vendor Product Version


To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix a null-ptr-deref in tipc_topsrv_accept\n\nsyzbot found a crash in tipc_topsrv_accept:\n\n  KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]\n  Workqueue: tipc_rcv tipc_topsrv_accept\n  RIP: 0010:kernel_accept+0x22d/0x350 net/socket.c:3487\n  Call Trace:\n   \u003cTASK\u003e\n   tipc_topsrv_accept+0x197/0x280 net/tipc/topsrv.c:460\n   process_one_work+0x991/0x1610 kernel/workqueue.c:2289\n   worker_thread+0x665/0x1080 kernel/workqueue.c:2436\n   kthread+0x2e4/0x3a0 kernel/kthread.c:376\n   ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306\n\nIt was caused by srv-\u003elistener that might be set to null by\ntipc_topsrv_stop() in net .exit whereas it\u0027s still used in\ntipc_topsrv_accept() worker.\n\nsrv-\u003elistener is protected by srv-\u003eidr_lock in tipc_topsrv_stop(), so add\na check for srv-\u003elistener under srv-\u003eidr_lock in tipc_topsrv_accept() to\navoid the null-ptr-deref. To ensure the lsock is not released during the\ntipc_topsrv_accept(), move sock_release() after tipc_topsrv_work_stop()\nwhere it\u0027s waiting until the tipc_topsrv_accept worker to be done.\n\nNote that sk_callback_lock is used to protect sk-\u003esk_user_data instead of\nsrv-\u003elistener, and it should check srv in tipc_topsrv_listener_data_ready()\ninstead. This also ensures that no more tipc_topsrv_accept worker will be\nstarted after tipc_conn_close() is called in tipc_topsrv_stop() where it\nsets sk-\u003esk_user_data to null."
    }
  ],
  "id": "CVE-2022-50555",
  "lastModified": "2025-10-08T19:38:32.610",
  "metrics": {},
  "published": "2025-10-07T16:15:43.850",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/24b129aed8730e48f47d852d58d76825ab6f407c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/32a3d4660b34ce49ac0162338ebe362098e2f5df"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7a939503fc32bff4ed60800b73ff7fbb4aea2142"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/82cb4e4612c633a9ce320e1773114875604a3cce"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ce69bdac2310152bb70845024d5d704c52aabfc3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/cedb41664e27b2cae7e21487f1bee22dcd84037d"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.