Vulnerability in Linux

[ Description ]Official description

In the Linux kernel, the following vulnerability has been resolved: RISC-V: KVM: Serialize IMSIC attributes with vCPU migration KVM device ioctls are not serialized against KVM_RUN. As a result, kvm_riscv_aia_imsic_rw_attr() can snapshot the physical CPU and HGEI of an IMSIC VS-file before a concurrent vCPU migration releases it. The HGEI can then be allocated to another vCPU before imsic_vsfile_rw() uses the stale tuple. A GET or SET attribute may consequently access the new owner's interrupt file. Serialize the entire IMSIC attribute operation with the target vCPU mutex. This prevents the VS-file from being migrated and recycled until the attribute access completes. Acquire the mutex killably so that the device ioctl remains interruptible while waiting for KVM_RUN to finish.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• git.kernel.org/stable/c/6c2bcf6b173d4afed883cceea9d47f2c5194161d
• git.kernel.org/stable/c/71acbea44e78665ea90e3c310fca6bbdcc0252db
• git.kernel.org/stable/c/8ae12ccaec6ec74945d8c1ef39f2c1b8df779abc
• git.kernel.org/stable/c/a29c5d2dd2ef9a8617a9a6d5585696d5f149cd98
• git.kernel.org/stable/c/c525772c304c971b0d3a1f2898dedbae653efe90