CVE-2025-39768

In the Linux kernel, the following vulnerability has been resolved:

net/mlx5: HWS, fix complex rules rehash error flow

Moving rules from matcher to matcher should not fail. However, if it does fail due to various reasons, the error flow should allow the kernel to continue functioning (albeit with broken steering rules) instead of going into series of soft lock-ups or some other problematic behaviour.

Similar to the simple rules, complex rules rehash logic suffers from the same problems. This patch fixes the error flow for moving complex rules:

• If new rule creation fails before it was even enqeued, do not poll for completion
• If TIMEOUT happened while moving the rule, no point trying to poll for completions for other rules. Something is broken, completion wont come, just abort the rehash sequence.
• If some other completion with error received, dont give up. Continue handling rest of the rules to minimize the damage.
• Make sure that the first error code that was received will be actually returned to the caller instead of replacing it with the generic error code.

All the aforementioned issues stem from the same bad error flow, so no point fixing them one by one and leaving partially broken code - fixing them in one patch.

Weakness

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

Affected Software

Extended Description

While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.

Potential Mitigations

References

• https://git.kernel.org/stable/c/37d54bc28d092bc3b314da45d730f00e9d86ec2a
• https://git.kernel.org/stable/c/4a842b1bf18a32ee0c25dd6dd98728b786a76fe4