CVE-2023-54225 net: ipa: only reset hashed tables when supported
A reference count underflow in the Linux kernel IPA driver can cause a denial of service during modem shutdown when hashed tables are unsupported.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-54225?
CVE-2023-54225 is a denial of service vulnerability in Linux, published on 30 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net: ipa: only reset hashed tables when supported
Last year, the code that manages GSI channel transactions switched from using spinlock-protected linked lists to using indexes into the ring buffer used for a channel. Recently, Google reported seeing transaction reference count underflows occasionally during shutdown.
Doug Anderson found a way to reproduce the issue reliably, and bisected the issue to the commit that eliminated the linked lists and the lock. The root cause was ultimately determined to be related to unused transactions being committed as part of the modem shutdown cleanup activity. Unused transactions are not normally expected (except in error cases).
The modem uses some ranges of IPA-resident memory, and whenever it shuts down we zero those ranges. In ipa_filter_reset_table() a transaction is allocated to zero modem filter table entries. If hashing is not supported, hashed table memory should not be zeroed. But currently nothing prevents that, and the result is an unused transaction. Something similar occurs when we zero routing table entries for the modem.
By preventing any attempt to clear hashed tables when hashing is not supported, the reference count underflow is avoided in this case.
Note that there likely remains an issue with properly freeing unused transactions (if they occur due to errors). This patch addresses only the underflows that Google originally reported.
Which versions are affected by CVE-2023-54225?
How do I fix CVE-2023-54225?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-54225 being exploited?
There is no known exploitation of CVE-2023-54225 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54225, DEBIAN-CVE-2023-54225, GHSA-r948-fj9p-588x, UBUNTU-CVE-2023-54225.