CVE-2021-4145

Se encontró un problema de desreferencia de puntero NULL en la capa de réplica de bloques de QEMU en versiones anteriores a 6.2.0. El puntero "self" es dereferenciado en mirror_wait_on_conflicts() sin asegurar que no sea NULL. Un usuario malicioso no privilegiado dentro del huésped podría usar este fallo para bloquear el proceso de QEMU en el host cuando la escritura de datos alcanza el umbral del nodo de reflejo

A NULL pointer dereference issue was found in the block mirror layer of QEMU. The `self` pointer is dereferenced in mirror_wait_on_conflicts() without ensuring that it's not NULL. A malicious unprivileged user within the guest could use this flaw to crash the QEMU process on the host when writing data reaches the threshold of mirroring node.

Kernel-based Virtual Machine offers a full virtualization solution for Linux on numerous hardware platforms. The virt:rhel module contains packages which provide user-space components used to run virtual machines using KVM. The packages also provide APIs for managing and interacting with the virtualized systems. Issues addressed include buffer overflow, integer overflow, null pointer, out of bounds access, out of bounds read, and use-after-free vulnerabilities.