CVE-2026-23138

Summary

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

tracing: Add recursion protection in kernel stack trace recording

A bug was reported about an infinite recursion caused by tracing the rcu events with the kernel stack trace trigger enabled. The stack trace code called back into RCU which then called the stack trace again.

Expand the ftrace recursion protection to add a set of bits to protect events from recursion. Each bit represents the context that the event is in (normal, softirq, interrupt and NMI).

Have the stack trace code use the interrupt context to protect against recursion.

Note, the bug showed an issue in both the RCU code as well as the tracing stacktrace code. This only handles the tracing stack trace side of the bug. The RCU fix will be handled separately.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 9b03768037d91ce727effb1c5d92d2c7781bf692affected
LinuxLinux5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 19e18e6dabb1bbba76d2809ca7d8ae9e1f5975feaffected
LinuxLinux5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 5b7f91acffd2c4c000971553d22efa1e1bb4feaeaffected
LinuxLinux5f5fa7ea89dc82d34ed458f4d7a8634e8e9eefce < 5f1ef0dfcb5b7f4a91a9b0e0ba533efd9f7e2cdbaffected
LinuxLinux5.8affected
LinuxLinux0 < 5.8unaffected
LinuxLinux6.6.130 <= 6.6.*unaffected
LinuxLinux6.12.78 <= 6.12.*unaffected
LinuxLinux6.18.6 <= 6.18.*unaffected
LinuxLinux6.19 <= *unaffected

Weaknesses

References