{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2022-48842",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nice: Fix race condition during interface enslave\n\nCommit 5dbbbd01cbba83 (\"ice: Avoid RTNL lock when re-creating\nauxiliary device\") changes a process of re-creation of aux device\nso ice_plug_aux_dev() is called from ice_service_task() context.\nThis unfortunately opens a race window that can result in dead-lock\nwhen interface has left LAG and immediately enters LAG again.\n\nReproducer:\n```\n#!/bin/sh\n\nip link add lag0 type bond mode 1 miimon 100\nip link set lag0\n\nfor n in {1..10}; do\n        echo Cycle: $n\n        ip link set ens7f0 master lag0\n        sleep 1\n        ip link set ens7f0 nomaster\ndone\n```\n\nThis results in:\n[20976.208697] Workqueue: ice ice_service_task [ice]\n[20976.213422] Call Trace:\n[20976.215871]  __schedule+0x2d1/0x830\n[20976.219364]  schedule+0x35/0xa0\n[20976.222510]  schedule_preempt_disabled+0xa/0x10\n[20976.227043]  __mutex_lock.isra.7+0x310/0x420\n[20976.235071]  enum_all_gids_of_dev_cb+0x1c/0x100 [ib_core]\n[20976.251215]  ib_enum_roce_netdev+0xa4/0xe0 [ib_core]\n[20976.256192]  ib_cache_setup_one+0x33/0xa0 [ib_core]\n[20976.261079]  ib_register_device+0x40d/0x580 [ib_core]\n[20976.266139]  irdma_ib_register_device+0x129/0x250 [irdma]\n[20976.281409]  irdma_probe+0x2c1/0x360 [irdma]\n[20976.285691]  auxiliary_bus_probe+0x45/0x70\n[20976.289790]  really_probe+0x1f2/0x480\n[20976.298509]  driver_probe_device+0x49/0xc0\n[20976.302609]  bus_for_each_drv+0x79/0xc0\n[20976.306448]  __device_attach+0xdc/0x160\n[20976.310286]  bus_probe_device+0x9d/0xb0\n[20976.314128]  device_add+0x43c/0x890\n[20976.321287]  __auxiliary_device_add+0x43/0x60\n[20976.325644]  ice_plug_aux_dev+0xb2/0x100 [ice]\n[20976.330109]  ice_service_task+0xd0c/0xed0 [ice]\n[20976.342591]  process_one_work+0x1a7/0x360\n[20976.350536]  worker_thread+0x30/0x390\n[20976.358128]  kthread+0x10a/0x120\n[20976.365547]  ret_from_fork+0x1f/0x40\n...\n[20976.438030] task:ip              state:D stack:    0 pid:213658 ppid:213627 flags:0x00004084\n[20976.446469] Call Trace:\n[20976.448921]  __schedule+0x2d1/0x830\n[20976.452414]  schedule+0x35/0xa0\n[20976.455559]  schedule_preempt_disabled+0xa/0x10\n[20976.460090]  __mutex_lock.isra.7+0x310/0x420\n[20976.464364]  device_del+0x36/0x3c0\n[20976.467772]  ice_unplug_aux_dev+0x1a/0x40 [ice]\n[20976.472313]  ice_lag_event_handler+0x2a2/0x520 [ice]\n[20976.477288]  notifier_call_chain+0x47/0x70\n[20976.481386]  __netdev_upper_dev_link+0x18b/0x280\n[20976.489845]  bond_enslave+0xe05/0x1790 [bonding]\n[20976.494475]  do_setlink+0x336/0xf50\n[20976.502517]  __rtnl_newlink+0x529/0x8b0\n[20976.543441]  rtnl_newlink+0x43/0x60\n[20976.546934]  rtnetlink_rcv_msg+0x2b1/0x360\n[20976.559238]  netlink_rcv_skb+0x4c/0x120\n[20976.563079]  netlink_unicast+0x196/0x230\n[20976.567005]  netlink_sendmsg+0x204/0x3d0\n[20976.570930]  sock_sendmsg+0x4c/0x50\n[20976.574423]  ____sys_sendmsg+0x1eb/0x250\n[20976.586807]  ___sys_sendmsg+0x7c/0xc0\n[20976.606353]  __sys_sendmsg+0x57/0xa0\n[20976.609930]  do_syscall_64+0x5b/0x1a0\n[20976.613598]  entry_SYSCALL_64_after_hwframe+0x65/0xca\n\n1. Command 'ip link ... set nomaster' causes that ice_plug_aux_dev()\n   is called from ice_service_task() context, aux device is created\n   and associated device->lock is taken.\n2. Command 'ip link ... set master...' calls ice's notifier under\n   RTNL lock and that notifier calls ice_unplug_aux_dev(). That\n   function tries to take aux device->lock but this is already taken\n   by ice_plug_aux_dev() in step 1\n3. Later ice_plug_aux_dev() tries to take RTNL lock but this is already\n   taken in step 2\n4. Dead-lock\n\nThe patch fixes this issue by following changes:\n- Bit ICE_FLAG_PLUG_AUX_DEV is kept to be set during ice_plug_aux_dev()\n  call in ice_service_task()\n- The bit is checked in ice_clear_rdma_cap() and only if it is not set\n  then ice_unplug_aux_dev() is called. If it is set (in other words\n  plugging of aux device was requested and ice_plug_aux_dev() is\n  potentially running) then the function only clears the\n---truncated---"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "1da177e4c3f4",
                                            "version_value": "a9bbacc53d1f"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.15.30",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.16.16",
                                                        "lessThanOrEqual": "5.16.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.17",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/a9bbacc53d1f5ed8febbfdf31401d20e005f49ef",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/a9bbacc53d1f5ed8febbfdf31401d20e005f49ef"
            },
            {
                "url": "https://git.kernel.org/stable/c/e1014fc5572375658fa421531cedb6e084f477dc",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/e1014fc5572375658fa421531cedb6e084f477dc"
            },
            {
                "url": "https://git.kernel.org/stable/c/5cb1ebdbc4342b1c2ce89516e19808d64417bdbc",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/5cb1ebdbc4342b1c2ce89516e19808d64417bdbc"
            }
        ]
    },
    "generator": {
        "engine": "bippy-c9c4e1df01b2"
    }
}