CVE-2022-50241
What it is
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix use-after-free on source server when doing inter-server copy Use-after-free occurred when the laundromat tried to free expired cpntf_state entry on the s2s_cp_stateids list after inter-server copy completed. The sc_cp_list that the expired copy state was inserted on was already freed. When COPY completes, the Linux client normally sends LOCKU(lock_state x), FREE_STATEID(lock_state x) and CLOSE(open_state y) to the source server. The nfs4_put_stid call from nfsd4_free_stateid cleans up the copy state from the s2s_cp_stateids list before freeing the lock state's stid. However, sometimes the CLOSE was sent before the FREE_STATEID request. When this happens, the nfsd4_close_open_stateid call from nfsd4_close frees all lock states on its st_locks list without cleaning up the copy state on the sc_cp_list list. When the time the FREE_STATEID arrives the server returns BAD_STATEID since the lock state was freed. This causes the use-after-free error to occur when the laundromat tries to free the expired cpntf_state. This patch adds a call to nfs4_free_cpntf_statelist in nfsd4_close_open_stateid to clean up the copy state before calling free_ol_stateid_reaplist to free the lock state's stid on the reaplist.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 8.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 5.10.150
- Linux Kernel < 5.15.75
- Linux Kernel < 5.19.17
- Linux Kernel < 6.0.3
Attack profile CVSS 3.1 · 8.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-50241.md and follow it. Check whether this project is affected by CVE-2022-50241. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/019805fea91599b22dfa62ffb29c022f35abeb06
- https://git.kernel.org/stable/c/35aa0fb8c3033a3d78603356e96fc18c5b9cceb2
- https://git.kernel.org/stable/c/6ea71246b7a02af675d733e72d14bd0d591d5f4a
- https://git.kernel.org/stable/c/83b94969751a691347606dbe6b1865efcfa5a643
- https://git.kernel.org/stable/c/bbacfcde5fff25ac22597e8373a065c647da6738
References
- https://git.kernel.org/stable/c/019805fea91599b22dfa62ffb29c022f35abeb06
- https://git.kernel.org/stable/c/35aa0fb8c3033a3d78603356e96fc18c5b9cceb2
- https://git.kernel.org/stable/c/6ea71246b7a02af675d733e72d14bd0d591d5f4a
- https://git.kernel.org/stable/c/83b94969751a691347606dbe6b1865efcfa5a643
- https://git.kernel.org/stable/c/bbacfcde5fff25ac22597e8373a065c647da6738