CVE-2024-47679vfs: fix race between evice_inodes() and find_inode()&iput()
- 7.8HighCVSS base score
- 0.20%Exploitation in 30 daysEPSS · top 90% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: vfs: fix race between evice_inodes() and find_inode()&iput() Hi, all Recently I noticed a bug[1] in btrfs, after digged it into and I believe it'a race in vfs. Let's assume there's a inode (ie ino 261) with i_count 1 is called by iput(), and there's a concurrent thread calling generic_shutdown_super(). cpu0: cpu1: iput() // i_count is 1 ->spin_lock(inode) ->dec i_count to 0 ->iput_final() generic_shutdown_super() ->__inode_add_lru() ->evict_inodes() // cause some reason[2] ->if (atomic_read(inode->i_count)) continue; // return before // inode 261 passed the above check // list_lru_add_obj() // and then schedule out ->spin_unlock() // note here: the inode 261 // was still at sb list and hash list, // and I_FREEING|I_WILL_FREE was not been set btrfs_iget() // after some function calls ->find_inode() // found the above inode 261 ->spin_lock(inode) // check I_FREEING|I_WILL_FREE // and passed ->__iget() ->spin_unlock(inode) // schedule back ->spin_lock(inode) // check (I_NEW|I_FREEING|I_WILL_FREE) flags, // passed and set I_FREEING iput() ->spin_unlock(inode) ->spin_lock(inode) ->evict() // dec i_count to 0 ->iput_final() ->spin_unlock() ->evict() Now, we have two threads simultaneously evicting the same inode, which may trigger the BUG(inode->i_state & I_CLEAR) statement both within clear_inode() and iput(). To fix the bug, recheck the inode->i_count after holding i_lock. Because in the most scenarios, the first check is valid, and the overhead of spin_lock() can be reduced. If there is any misunderstanding, please let me know, thanks. [1]: https://lore.kernel.org/linux-btrfs/[email protected]/ [2]: The reason might be 1. SB_ACTIVE was removed or 2. mapping_shrinkable() return false when I reproduced the bug.
Timeline
ID reserved
By Linux
- 21 days later
· 21 days later
Published
- 22 months later
· 22 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.20% · top 90% of all CVEs (14 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: High 7.8.
Affected products
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 6cc13a80a26e6b48f78c725c01b91987d61563ef
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 489faddb1ae75b0e1a741fe5ca2542a2b5e794a5
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 47a68c75052a660e4c37de41e321582ec9496195
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 3721a69403291e2514d13a7c3af50a006ea1153b
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 540fb13120c9eab3ef203f90c00c8e69f37449d1
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 0eed942bc65de1f93eca7bda51344290f9c573bb
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 0f8a5b6d0dafa4f533ac82e98f8b812073a7c9d1
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 6c857fb12b9137fee574443385d53914356bbe11
- affected 63997e98a3be68d7cec806d22bf9b02b2e1daabb – < 88b1afbf0f6b221f6c5bb66cc80cd3b38d696687
- affected 2.6.37
- unaffected < 2.6.37
- unaffected 4.19.323 – ≤ 4.19.*
- unaffected 5.4.285 – ≤ 5.4.*
- unaffected 5.10.227 – ≤ 5.10.*
- unaffected 5.15.168 – ≤ 5.15.*
- unaffected 6.1.113 – ≤ 6.1.*
- unaffected 6.6.54 – ≤ 6.6.*
- unaffected 6.10.13 – ≤ 6.10.*
- unaffected 6.11.2 – ≤ 6.11.*
- unaffected 6.12 – ≤ *
References
References11
- https://git.kernel.org/stable/c/6cc13a80a26e6b48f78c725c01b91987d61563ef (opens in a new tab)
- https://git.kernel.org/stable/c/489faddb1ae75b0e1a741fe5ca2542a2b5e794a5 (opens in a new tab)
- https://git.kernel.org/stable/c/47a68c75052a660e4c37de41e321582ec9496195 (opens in a new tab)
- https://git.kernel.org/stable/c/3721a69403291e2514d13a7c3af50a006ea1153b (opens in a new tab)
- https://git.kernel.org/stable/c/540fb13120c9eab3ef203f90c00c8e69f37449d1 (opens in a new tab)
- https://git.kernel.org/stable/c/0eed942bc65de1f93eca7bda51344290f9c573bb (opens in a new tab)
- https://git.kernel.org/stable/c/0f8a5b6d0dafa4f533ac82e98f8b812073a7c9d1 (opens in a new tab)
- https://git.kernel.org/stable/c/6c857fb12b9137fee574443385d53914356bbe11 (opens in a new tab)
- https://git.kernel.org/stable/c/88b1afbf0f6b221f6c5bb66cc80cd3b38d696687 (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html (opens in a new tab)
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-2024-42600 (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
[](https://cveledger.app/cve/CVE-2024-47679)Record last updated .