CVE-2025-38270

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

net: drv: netdevsim: don't napi_complete() from netpoll

netdevsim supports netpoll. Make sure we don't call napi_complete() from it, since it may not be scheduled. Breno reports hitting a warning in napi_complete_done():

WARNING: CPU: 14 PID: 104 at net/core/dev.c:6592 napi_complete_done+0x2cc/0x560 __napi_poll+0x2d8/0x3a0 handle_softirqs+0x1fe/0x710

This is presumably after netpoll stole the SCHED bit prematurely.

A missing check in the netdevsim NAPI poll function could lead to a warning or soft crash when used with netpoll, due to premature calls to napi_complete() without verifying scheduling state. This issue is mitigated by replacing the call with napi_complete_done() only if the budget is not exceeded. While the issue is non-exploitable in practice and difficult to trigger, it can impact system availability.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.