CVE-2024-39476md/raid5: fix deadlock that raid5d() wait for itself to clear MD_SB_CHANGE_PENDING

Description

In the Linux kernel, the following vulnerability has been resolved: md/raid5: fix deadlock that raid5d() wait for itself to clear MD_SB_CHANGE_PENDING Xiao reported that lvm2 test lvconvert-raid-takeover.sh can hang with small possibility, the root cause is exactly the same as commit bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") However, Dan reported another hang after that, and junxiao investigated the problem and found out that this is caused by plugged bio can't issue from raid5d(). Current implementation in raid5d() has a weird dependence: 1) md_check_recovery() from raid5d() must hold 'reconfig_mutex' to clear MD_SB_CHANGE_PENDING; 2) raid5d() handles IO in a deadloop, until all IO are issued; 3) IO from raid5d() must wait for MD_SB_CHANGE_PENDING to be cleared; This behaviour is introduce before v2.6, and for consequence, if other context hold 'reconfig_mutex', and md_check_recovery() can't update super_block, then raid5d() will waste one cpu 100% by the deadloop, until 'reconfig_mutex' is released. Refer to the implementation from raid1 and raid10, fix this problem by skipping issue IO if MD_SB_CHANGE_PENDING is still set after md_check_recovery(), daemon thread will be woken up when 'reconfig_mutex' is released. Meanwhile, the hang problem will be fixed as well.

Timeline

Scores

EPSS (exploitation in 30 days)

0.18% · top 93% of all CVEs (15 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.

Affected products

• Linux · Linux

  • affected f3d55bd5b7b928ad82f8075d89c908702f3593ab – < b32aa95843cac6b12c2c014d40fca18aef24a347
  • affected 1c00bb624cd084e2006520ad0edacaff0fb941c4 – < 634ba3c97ec413cb10681c7b196db43ee461ecf4
  • affected 782b3e71c957991ac8ae53318bc369049d49bb53 – < aa64464c8f4d2ab92f6d0b959a1e0767b829d787
  • affected 9e86dffd0b02594d2e7c60c6db9e889c0395414b – < 098d54934814dd876963abfe751c3b1cf7fbe56a
  • affected 5e2cf333b7bd5d3e62595a44d598a254c697cd74 – < 3f8d5e802d4cedd445f9a89be8c3fd2d0e99024b
  • affected 5e2cf333b7bd5d3e62595a44d598a254c697cd74 – < cd2538e5af495b3c747e503db346470fc1ffc447
  • affected 5e2cf333b7bd5d3e62595a44d598a254c697cd74 – < e332a12f65d8fed8cf63bedb4e9317bb872b9ac7
  • affected 5e2cf333b7bd5d3e62595a44d598a254c697cd74 – < 151f66bb618d1fd0eeb84acb61b4a9fa5d8bb0fa
  • affected 7d808fe6af8409cf9f46ed2b10840e5788985e9b
  • affected 2cab058f2b147e0b7c01546ba00445e5701861f5
  • affected 91962e40ec3d26e291db230cd45b302da2aff200
  • affected 4.19.262 – < 4.19.316
  • affected 5.4.220 – < 5.4.278
  • affected 5.10.150 – < 5.10.219
  • affected 5.15.75 – < 5.15.161
  • affected 4.14.296 – < 4.15
  • affected 5.19.17 – < 5.20
  • affected 6.0.3 – < 6.1

• Linux · Linux

  • affected 6.1
  • unaffected < 6.1
  • unaffected 4.19.316 – ≤ 4.19.*
  • unaffected 5.4.278 – ≤ 5.4.*
  • unaffected 5.10.219 – ≤ 5.10.*
  • unaffected 5.15.161 – ≤ 5.15.*
  • unaffected 6.1.94 – ≤ 6.1.*
  • unaffected 6.6.34 – ≤ 6.6.*
  • unaffected 6.9.5 – ≤ 6.9.*
  • unaffected 6.10 – ≤ *

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2024-38001 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2024-39476](https://cveledger.app/badge/CVE-2024-39476.svg)](https://cveledger.app/cve/CVE-2024-39476)

Record last updated 23 May 2026, 15:50 UTC.