CVE-2022-48658 mm: slub: fix flush_cpu_slab()/__free_slab() invocations in task context.

2024-04-2813:01:12

Linux

www.cve.org

linux kernel

vulnerability

fix

flush_cpu_slab

__free_slab

task context

irq context

workqueue

dependency issue

wq_mem_reclaim

nvme_delete_ctrl_work

nvme_core

AI Score

7.6

Confidence

High

EPSS

Percentile

5.1%

JSON

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

mm: slub: fix flush_cpu_slab()/__free_slab() invocations in task context.

Commit 5a836bf6b09f (“mm: slub: move flush_cpu_slab() invocations
__free_slab() invocations out of IRQ context”) moved all flush_cpu_slab()
invocations to the global workqueue to avoid a problem related
with deactivate_slab()/__free_slab() being called from an IRQ context
on PREEMPT_RT kernels.

When the flush_all_cpu_locked() function is called from a task context
it may happen that a workqueue with WQ_MEM_RECLAIM bit set ends up
flushing the global workqueue, this will cause a dependency issue.

workqueue: WQ_MEM_RECLAIM nvme-delete-wq:nvme_delete_ctrl_work [nvme_core]
is flushing !WQ_MEM_RECLAIM events:flush_cpu_slab
WARNING: CPU: 37 PID: 410 at kernel/workqueue.c:2637
check_flush_dependency+0x10a/0x120
Workqueue: nvme-delete-wq nvme_delete_ctrl_work [nvme_core]
RIP: 0010:check_flush_dependency+0x10a/0x120[ 453.262125] Call Trace:
__flush_work.isra.0+0xbf/0x220
? __queue_work+0x1dc/0x420
flush_all_cpus_locked+0xfb/0x120
__kmem_cache_shutdown+0x2b/0x320
kmem_cache_destroy+0x49/0x100
bioset_exit+0x143/0x190
blk_release_queue+0xb9/0x100
kobject_cleanup+0x37/0x130
nvme_fc_ctrl_free+0xc6/0x150 [nvme_fc]
nvme_free_ctrl+0x1ac/0x2b0 [nvme_core]

Fix this bug by creating a workqueue for the flush operation with
the WQ_MEM_RECLAIM bit set.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "mm/slub.c"
    ],
    "versions": [
      {
        "version": "5a836bf6b09f",
        "lessThan": "61703b248be9",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "5a836bf6b09f",
        "lessThan": "df6cb39335cf",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "5a836bf6b09f",
        "lessThan": "e45cc288724f",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "mm/slub.c"
    ],
    "versions": [
      {
        "version": "5.15",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.15",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.71",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.19.12",
        "lessThanOrEqual": "5.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.0",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]