{
  "cveId": "CVE-2023-52587",
  "url": "https://patchblox.com/security/cve/CVE-2023-52587",
  "summary": "CVE-2023-52587 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-52587, released March 6, 2024. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  IB/ipoib: Fix mcast list locking  Releasing the...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  IB/ipoib: Fix mcast list locking  Releasing the \u0060priv-\u003Elock\u0060 while iterating the \u0060priv-\u003Emulticast_list\u0060 in \u0060ipoib_mcast_join_task()\u0060 opens a window for \u0060ipoib_mcast_dev_flush()\u0060 to remove the items while in the middle of iteration. If the mcast is removed while the lock was dropped, the for loop spins forever resulting in a hard lockup (as was reported on RHEL 4.18.0-372.75.1.el8_6 kernel):      Task A (kworker/u72:2 below)       | Task B (kworker/u72:0 below)     -----------------------------------\u002B-----------------------------------     ipoib_mcast_join_task(work)        | ipoib_ib_dev_flush_light(work)       spin_lock_irq(\u0026priv-\u003Elock)       | __ipoib_ib_dev_flush(priv, ...)       list_for_each_entry(mcast,       | ipoib_mcast_dev_flush(dev = priv-\u003Edev)           \u0026priv-\u003Emulticast_list, list) |         ipoib_mcast_join(dev, mcast)   |           spin_unlock_irq(\u0026priv-\u003Elock) |                                        |   spin_lock_irqsave(\u0026priv-\u003Elock, flags)                                        |   list_for_each_entry_safe(mcast, tmcast,                                        |                  \u0026priv-\u003Emulticast_list, list)                                        |     list_del(\u0026mcast-\u003Elist);                                        |     list_add_tail(\u0026mcast-\u003Elist, \u0026remove_list)                                        |   spin_unlock_irqrestore(\u0026priv-\u003Elock, flags)           spin_lock_irq(\u0026priv-\u003Elock)   |                                        |   ipoib_mcast_remove_list(\u0026remove_list)    (Here, \u0060mcast\u0060 is no longer on the  |     list_for_each_entry_safe(mcast, tmcast,     \u0060priv-\u003Emulticast_list\u0060 and we keep |                            remove_list, list)     spinning on the \u0060remove_list\u0060 of   |  \u003E\u003E\u003E  wait_for_completion(\u0026mcast-\u003Edone)     the other thread which is blocked  |     and the list is still valid on     |     it\u0027s stack.)  Fix this by keeping the lock held and changing to GFP_ATOMIC to prevent eventual sleeps. Unfortunately we could not reproduce the lockup and confirm this fix but based on the code review I think this fix should address such lockups.  crash\u003E bc 31 PID: 747      TASK: ff1c6a1a007e8000  CPU: 31   COMMAND: \u0022kworker/u72:2\u0022 --     [exception RIP: ipoib_mcast_join_task\u002B0x1b1]     RIP: ffffffffc0944ac1  RSP: ff646f199a8c7e00  RFLAGS: 00000002     RAX: 0000000000000000  RBX: ff1c6a1a04dc82f8  RCX: 0000000000000000                                   work (\u0026priv-\u003Emcast_task{,.work})     RDX: ff1c6a192d60ac68  RSI: 0000000000000286  RDI: ff1c6a1a04dc8000            \u0026mcast-\u003Elist     RBP: ff646f199a8c7e90   R8: ff1c699980019420   R9: ff1c6a1920c9a000     R10: ff646f199a8c7e00  R11: ff1c6a191a7d9800  R12: ff1c6a192d60ac00                                                          mcast     R13: ff1c6a1d82200000  R14: ff1c6a1a04dc8000  R15: ff1c6a1a04dc82d8            dev                    priv (\u0026priv-\u003Elock)     \u0026priv-\u003Emulticast_list (aka head)     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018 --- \u003CNMI exception stack\u003E ---  #5 [ff646f199a8c7e00] ipoib_mcast_join_task\u002B0x1b1 at ffffffffc0944ac1 [ib_ipoib]  #6 [ff646f199a8c7e98] process_one_work\u002B0x1a7 at ffffffff9bf10967  crash\u003E rx ff646f199a8c7e68 ff646f199a8c7e68:  ff1c6a1a04dc82f8 \u003C\u003C\u003C work = \u0026priv-\u003Emcast_task.work  crash\u003E list -hO ipoib_dev_priv.multicast_list ff1c6a1a04dc8000 (empty)  crash\u003E ipoib_dev_priv.mcast_task.work.func,mcast_mutex.owner.counter ff1c6a1a04dc8000   mcast_task.work.func = 0xffffffffc0944910 \u003Cipoib_mcast_join_task\u003E,   mcast_mutex.owner.counter = 0xff1c69998efec000  crash\u003E b 8 PID: 8        TASK: ff1c69998efec000  CPU: 33   COMMAND: \u0022kworker/u72:0\u0022 --  #3 [ff646f1980153d50] wait_for_completion\u002B0x96 at ffffffff9c7d7646  #4 [ff646f1980153d90] ipoib_mcast_remove_list\u002B0x56 at ffffffffc0944dc6 [ib_ipoib]  #5 [ff646f1980153de8] ipoib_mcast_dev_flush\u002B0x1a7 at ffffffffc09455a7 [ib_ipoib]  #6 [ff646f1980153e58] __ipoib_ib_dev_flush\u002B0x1a4 at ffffffffc09431a4 [ib_ipoib]  #7 [ff ---truncated---",
  "published": "2024-03-06T07:15:07Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00309,
  "epssPercentile": 0.23917,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.1.82-1",
      "fix": "DEBIAN-CVE-2023-52587",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-52587",
      "released": "2024-03-06T07:15:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.7.7-1",
      "fix": "DEBIAN-CVE-2023-52587",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-52587",
      "released": "2024-03-06T07:15:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.7.7-1",
      "fix": "DEBIAN-CVE-2023-52587",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-52587",
      "released": "2024-03-06T07:15:07Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T07:25:28Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}