GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-Q2CP-MH84-P47V

Vulnerability from github – Published: 2024-05-20 12:30 – Updated: 2025-01-14 18:31
VLAI
Details

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

raid1: fix use-after-free for original bio in raid1_write_request()

r1_bio->bios[] is used to record new bios that will be issued to underlying disks, however, in raid1_write_request(), r1_bio->bios[] will set to the original bio temporarily. Meanwhile, if blocked rdev is set, free_r1bio() will be called causing that all r1_bio->bios[] to be freed:

raid1_write_request() r1_bio = alloc_r1bio(mddev, bio); -> r1_bio->bios[] is NULL for (i = 0; i < disks; i++) -> for each rdev in conf // first rdev is normal r1_bio->bios[0] = bio; -> set to original bio // second rdev is blocked if (test_bit(Blocked, &rdev->flags)) break

if (blocked_rdev) free_r1bio() put_all_bios() bio_put(r1_bio->bios[0]) -> original bio is freed

Test scripts:

mdadm -CR /dev/md0 -l1 -n4 /dev/sd[abcd] --assume-clean fio -filename=/dev/md0 -ioengine=libaio -rw=write -bs=4k -numjobs=1 \ -iodepth=128 -name=test -direct=1 echo blocked > /sys/block/md0/md/rd2/state

Test result:

BUG bio-264 (Not tainted): Object already free

Allocated in mempool_alloc_slab+0x24/0x50 age=1 cpu=1 pid=869 kmem_cache_alloc+0x324/0x480 mempool_alloc_slab+0x24/0x50 mempool_alloc+0x6e/0x220 bio_alloc_bioset+0x1af/0x4d0 blkdev_direct_IO+0x164/0x8a0 blkdev_write_iter+0x309/0x440 aio_write+0x139/0x2f0 io_submit_one+0x5ca/0xb70 __do_sys_io_submit+0x86/0x270 __x64_sys_io_submit+0x22/0x30 do_syscall_64+0xb1/0x210 entry_SYSCALL_64_after_hwframe+0x6c/0x74 Freed in mempool_free_slab+0x1f/0x30 age=1 cpu=1 pid=869 kmem_cache_free+0x28c/0x550 mempool_free_slab+0x1f/0x30 mempool_free+0x40/0x100 bio_free+0x59/0x80 bio_put+0xf0/0x220 free_r1bio+0x74/0xb0 raid1_make_request+0xadf/0x1150 md_handle_request+0xc7/0x3b0 md_submit_bio+0x76/0x130 __submit_bio+0xd8/0x1d0 submit_bio_noacct_nocheck+0x1eb/0x5c0 submit_bio_noacct+0x169/0xd40 submit_bio+0xee/0x1d0 blkdev_direct_IO+0x322/0x8a0 blkdev_write_iter+0x309/0x440 aio_write+0x139/0x2f0

Since that bios for underlying disks are not allocated yet, fix this problem by using mempool_free() directly to free the r1_bio.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2024-35979"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-20T10:15:12Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nraid1: fix use-after-free for original bio in raid1_write_request()\n\nr1_bio-\u003ebios[] is used to record new bios that will be issued to\nunderlying disks, however, in raid1_write_request(), r1_bio-\u003ebios[]\nwill set to the original bio temporarily. Meanwhile, if blocked rdev\nis set, free_r1bio() will be called causing that all r1_bio-\u003ebios[]\nto be freed:\n\nraid1_write_request()\n r1_bio = alloc_r1bio(mddev, bio); -\u003e r1_bio-\u003ebios[] is NULL\n for (i = 0;  i \u003c disks; i++) -\u003e for each rdev in conf\n  // first rdev is normal\n  r1_bio-\u003ebios[0] = bio; -\u003e set to original bio\n  // second rdev is blocked\n  if (test_bit(Blocked, \u0026rdev-\u003eflags))\n   break\n\n if (blocked_rdev)\n  free_r1bio()\n   put_all_bios()\n    bio_put(r1_bio-\u003ebios[0]) -\u003e original bio is freed\n\nTest scripts:\n\nmdadm -CR /dev/md0 -l1 -n4 /dev/sd[abcd] --assume-clean\nfio -filename=/dev/md0 -ioengine=libaio -rw=write -bs=4k -numjobs=1 \\\n    -iodepth=128 -name=test -direct=1\necho blocked \u003e /sys/block/md0/md/rd2/state\n\nTest result:\n\nBUG bio-264 (Not tainted): Object already free\n-----------------------------------------------------------------------------\n\nAllocated in mempool_alloc_slab+0x24/0x50 age=1 cpu=1 pid=869\n kmem_cache_alloc+0x324/0x480\n mempool_alloc_slab+0x24/0x50\n mempool_alloc+0x6e/0x220\n bio_alloc_bioset+0x1af/0x4d0\n blkdev_direct_IO+0x164/0x8a0\n blkdev_write_iter+0x309/0x440\n aio_write+0x139/0x2f0\n io_submit_one+0x5ca/0xb70\n __do_sys_io_submit+0x86/0x270\n __x64_sys_io_submit+0x22/0x30\n do_syscall_64+0xb1/0x210\n entry_SYSCALL_64_after_hwframe+0x6c/0x74\nFreed in mempool_free_slab+0x1f/0x30 age=1 cpu=1 pid=869\n kmem_cache_free+0x28c/0x550\n mempool_free_slab+0x1f/0x30\n mempool_free+0x40/0x100\n bio_free+0x59/0x80\n bio_put+0xf0/0x220\n free_r1bio+0x74/0xb0\n raid1_make_request+0xadf/0x1150\n md_handle_request+0xc7/0x3b0\n md_submit_bio+0x76/0x130\n __submit_bio+0xd8/0x1d0\n submit_bio_noacct_nocheck+0x1eb/0x5c0\n submit_bio_noacct+0x169/0xd40\n submit_bio+0xee/0x1d0\n blkdev_direct_IO+0x322/0x8a0\n blkdev_write_iter+0x309/0x440\n aio_write+0x139/0x2f0\n\nSince that bios for underlying disks are not allocated yet, fix this\nproblem by using mempool_free() directly to free the r1_bio.",
  "id": "GHSA-q2cp-mh84-p47v",
  "modified": "2025-01-14T18:31:49Z",
  "published": "2024-05-20T12:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-35979"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f28d49a328fe20926995d5fbdc92da665596268"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f423f41b7679c09abb26d2bd54be5cbef23c9446"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fcf3f7e2fc8a53a6140beee46ec782a4c88e4744"
    }
  ],
  "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"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

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

Author Source Type Date Other

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…