CVE-2022-50534

MEDIUM EPSS 4.3%
Published Oct 7, 20258mo ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Oct 7, 2025 8mo ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: dm thin: Use last transaction's pmd->root when commit failed Recently we found a softlock up problem in dm thin pool btree lookup code due to corrupted metadata: Kernel panic - not syncing: softlockup: hung tasks CPU: 7 PID: 2669225 Comm: kworker/u16:3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: dm-thin do_worker [dm_thin_pool] Call Trace: <IRQ> dump_stack+0x9c/0xd3 panic+0x35d/0x6b9 watchdog_timer_fn.cold+0x16/0x25 __run_hrtimer+0xa2/0x2d0 </IRQ> RIP: 0010:__relink_lru+0x102/0x220 [dm_bufio] __bufio_new+0x11f/0x4f0 [dm_bufio] new_read+0xa3/0x1e0 [dm_bufio] dm_bm_read_lock+0x33/0xd0 [dm_persistent_data] ro_step+0x63/0x100 [dm_persistent_data] btree_lookup_raw.constprop.0+0x44/0x220 [dm_persistent_data] dm_btree_lookup+0x16f/0x210 [dm_persistent_data] dm_thin_find_block+0x12c/0x210 [dm_thin_pool] __process_bio_read_only+0xc5/0x400 [dm_thin_pool] process_thin_deferred_bios+0x1a4/0x4a0 [dm_thin_pool] process_one_work+0x3c5/0x730 Following process may generate a broken btree mixed with fresh and stale btree nodes, which could get dm thin trapped in an infinite loop while looking up data block: Transaction 1: pmd->root = A, A->B->C // One path in btree pmd->root = X, X->Y->Z // Copy-up Transaction 2: X,Z is updated on disk, Y write failed. // Commit failed, dm thin becomes read-only. process_bio_read_only dm_thin_find_block __find_block dm_btree_lookup(pmd->root) The pmd->root points to a broken btree, Y may contain stale node pointing to any block, for example X, which gets dm thin trapped into a dead loop while looking up Z. Fix this by setting pmd->root in __open_metadata(), so that dm thin will use the last transaction's pmd->root if commit failed. Fetch a reproducer in [Link]. Linke: https://bugzilla.kernel.org/show_bug.cgi?id=216790

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
4.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 8

VendorProductVersionRange
linuxlinux_kernel*≥3.2  –  <4.9.337
linuxlinux_kernel*≥4.10  –  <4.14.303
linuxlinux_kernel*≥4.15  –  <4.19.270
linuxlinux_kernel*≥4.20  –  <5.4.229
linuxlinux_kernel*≥5.5  –  <5.10.163
linuxlinux_kernel*≥5.11  –  <5.15.87
linuxlinux_kernel*≥5.16  –  <6.0.18
linuxlinux_kernel*≥6.1  –  <6.1.4

References 9

  • git.kernel.org https://git.kernel.org/stable/c/3db757ffdd87ed8d7118b2250236a496502a660f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4b710e8481ade7c9200e94d3018e99dc42a0a0e8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7991dbff6849f67e823b7cc0c15e5a90b0549b9f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/87d69b8824ca9b090f5a8ed47f758e8f6eecb871
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/94f01ecc2aa0be992865acc80ebb6701f731f955
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a63ce4eca86fd207e3db07c00fb7ccf4adf1b230
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b35a22760aa5008d82533e59b0f0b5eb1b02d4e5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b91f481300e3a10eaf66b94fc39b740928762aaf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f758987ff0af3a4b5ee69e95cab6a5294e4367b0
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/3db757ffdd87ed8d7118b2250236a496502a660f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4b710e8481ade7c9200e94d3018e99dc42a0a0e8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7991dbff6849f67e823b7cc0c15e5a90b0549b9f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/87d69b8824ca9b090f5a8ed47f758e8f6eecb871
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/94f01ecc2aa0be992865acc80ebb6701f731f955
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a63ce4eca86fd207e3db07c00fb7ccf4adf1b230
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b35a22760aa5008d82533e59b0f0b5eb1b02d4e5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b91f481300e3a10eaf66b94fc39b740928762aaf
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f758987ff0af3a4b5ee69e95cab6a5294e4367b0
    Patch