Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix IRQ injection with SIGP Stop and Store Status
When __inject_sigp_stop() is called for a Stop and Store Status operation, if the vCPU is running, the interrupt is marked as pending and the status is stored by the thread performing the KVM_RUN IOCTL.
If the vCPU is already stopped, the status is stored immediately.
Storing the status means writing into userspace, which might fault, and __inject_sigp_stop() is called from do_inject_vcpu() which in turn is always called holding a spinlock, which is obviously an issue.
Fix this by returning -EWOULDBLOCK from __inject_sigp_stop(), and adding a bool flag to indicate whether a store status is needed. The callers of do_inject_vcpu() are modified to pass the pointer to the bool flag; whenever a Store Status operation is needed, the callers can now perform it outside the spinlock.
Opportunistically refactor kvm_s390_set_irq_state() to use scoped_guard() and __free().
[ Added Fixes tag while picking – Claudio ]
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 4.19.0 (+13 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Ubuntu 26.04 | Planned | — |