CVE-2021-3416

Se encontró un posible desbordamiento de la pila por medio de un problema de bucle infinito en varios emuladores de NIC de QEMU en versiones hasta 5.2.0 incluyéndola. El problema ocurre en el modo loopback de una NIC en donde son omitidas las comprobaciones DMA reentrantes. Un usuario y proceso invitado puede usar este fallo para consumir ciclos de CPU o bloquear el proceso QEMU en el host, resultando en un escenario DoS

A potential stack overflow via infinite loop issue was found in various NIC emulators of QEMU. The issue occurs in loopback mode of a NIC wherein reentrant DMA checks get bypassed. A guest user/process may use this flaw to consume CPU cycles or crash the QEMU process on the host resulting in DoS scenario.

An update that solves 15 vulnerabilities and has two fixes is now available. This update for qemu fixes the following issues. Fixed OOB access in sm501 device emulation. Fixed use-after-free in usb xhci packet handling. Fixed use-after-free in usb ehci packet handling. Fixed infinite loop in usb hcd-ohci emulation. Fixed OOB access in usb hcd-ohci emulation. Fixed guest triggerable assert in shared network handling code. Fixed infinite loop in e1000e device emulation. Fixed OOB access in atapi emulation. Fixed heap overflow in MSIx emulation. Fixed null pointer deref. In mmio ops. Fixed infinite loop in e1000 device emulation. Fixed OOB access in rtl8139 NIC emulation. Fixed OOB access in other NIC emulations. Fixed OOB access in ati-vga emulation. Fixed OOB access in SLIRP ARP/NCSI packet processing directories and log files SLE15-SP3, and openSUSE equivalents This update was imported from the SUSE:SLE-15-SP2:Update update project.