CVE-2024-36891

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: maple_tree: corrige la desreferencia del puntero nulo mas_empty_area_rev() Actualmente el código llama a mas_start() seguido de mas_data_end() si el estado del arce es MA_START, pero mas_start() puede regresar con el estado del arce nodo == NULL. Esto dará lugar a una desreferencia del puntero nulo al verificar la información en el nodo NULL, lo cual se realiza en mas_data_end(). Evite establecer el desplazamiento si no hay ningún nodo esperando hasta que se verifique el estado del arce para detectar un estado vacío o de entrada única. Un usuario podría desencadenar los eventos para causar un kernel ups al desasignar todos los vmas para producir un árbol de arce vacío y luego mapear un vma que causaría el escenario descrito anteriormente.

In the Linux kernel, the following vulnerability has been resolved: maple_tree: fix mas_empty_area_rev() null pointer dereference Currently the code calls mas_start() followed by mas_data_end() if the maple state is MA_START, but mas_start() may return with the maple state node == NULL. This will lead to a null pointer dereference when checking information in the NULL node, which is done in mas_data_end(). Avoid setting the offset if there is no node by waiting until after the maple state is checked for an empty or single entry state. A user could trigger the events to cause a kernel oops by unmapping all vmas to produce an empty maple tree, then mapping a vma that would cause the scenario described above.

Benedict Schlüter, Supraja Sridhara, Andrin Bertschi, and Shweta Shinde discovered that an untrusted hypervisor could inject malicious #VC interrupts and compromise the security guarantees of AMD SEV-SNP. This flaw is known as WeSee. A local attacker in control of the hypervisor could use this to expose sensitive information or possibly execute arbitrary code in the trusted execution environment. Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.