On Wed, Jul 02, 2025 at 08:29:45AM +0000, Xinyu Zheng wrote:
From: Dongli Zhang dongli.zhang@oracle.com
[ Upstream commit f591cf9fce724e5075cc67488c43c6e39e8cbe27 ]
The vhost-scsi completion path may access vq->log_base when vq->log_used is already set to false.
vhost-thread QEMU-threadvhost_scsi_complete_cmd_work() -> vhost_add_used() -> vhost_add_used_n() if (unlikely(vq->log_used)) QEMU disables vq->log_used via VHOST_SET_VRING_ADDR. mutex_lock(&vq->mutex); vq->log_used = false now! mutex_unlock(&vq->mutex);
QEMU gfree(vq->log_base) log_used() -> log_write(vq->log_base)Assuming the VMM is QEMU. The vq->log_base is from QEMU userpace and can be reclaimed via gfree(). As a result, this causes invalid memory writes to QEMU userspace.
The control queue path has the same issue.
CVE-2025-38074
This is not needed.
Cc: stable@vger.kernel.org#5.10.x
What about 5.15.y and 6.1.y? We can't take a patch just for 5.10 as that would cause regressions, right?
Please provide all relevant backports and I will be glad to queue them up then. I'll drop this from my queue for now, thanks.
greg k-h