CVE-2023-42467

QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately.

Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm packages provide the user-space component for running virtual machines that use KVM.

Security Fix(es):

• QEMU: e1000e: heap use-after-free in e1000e_write_packet_to_guest() (CVE-2023-3019)
• QEMU: VNC: infinite loop in inflate_buffer() leads to denial of service (CVE-2023-3255)
• QEMU: improper IDE controller reset can lead to MBR overwrite (CVE-2023-5088)
• QEMU: VNC: NULL pointer dereference in qemu_clipboard_request() (CVE-2023-6683)
• QEMU: am53c974: denial of service due to division by zero (CVE-2023-42467)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

• CVE-2023-3019: net: improper synchronization in net device backends
• CVE-2023-42467: scsi-disk: division by zero in scsi_disk_emulate_mode_select
• CVE-2024-26327: pcie_sriov: NumVFs validation buffer overflow

QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately.

A flaw was found in the QEMU implementation of VMWare's paravirtual RDMA device. This flaw allows a crafted guest driver to allocate and initialize a huge number of page tables to be used as a ring of descriptors for CQ and async events, potentially leading to an out-of-bounds read and crash of QEMU. (CVE-2023-1544) A DMA reentrancy issue leading to a use-after-free error was found in the e1000e NIC emulation code in QEMU. This issue could allow a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. (CVE-2023-3019) A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the inflate_buffer function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service. (CVE-2023-3255) A bug in QEMU could cause a guest I/O operation otherwise addressed to an arbitrary disk offset to be targeted to offset 0 instead (potentially overwriting the VM's boot code). This could be used, for example, by L2 guests with a virtual disk (vdiskL2) stored on a virtual disk of an L1 (vdiskL1) hypervisor to read and/or write data to LBA 0 of vdiskL1, potentially gaining control of L1 at its next reboot. (CVE-2023-5088) A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard peer, leading to a NULL pointer dereference. This could allow a malicious authenticated VNC client to crash QEMU and trigger a denial of service. (CVE-2023-6683) A stack based buffer overflow was found in the virtio-net device of QEMU. This issue occurs when flushing TX in the virtio_net_flush_tx function if guest features VIRTIO_NET_F_HASH_REPORT, VIRTIO_F_VERSION_1 and VIRTIO_NET_F_MRG_RXBUF are enabled. This could allow a malicious user to overwrite local variables allocated on the stack. Specifically, the out_sg variable could be used to read a part of process memory and send it to the wire, causing an information leak. (CVE-2023-6693) QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately. (CVE-2023-42467) QEMU before 8.2.0 has an integer underflow, and resultant buffer overflow, via a TI command when an expected non-DMA transfer length is less than the length of the available FIFO data. This occurs in esp_do_nodma in hw/scsi/esp.c because of an underflow of async_len. (CVE-2024-24474) An issue was discovered in QEMU 7.1.0 through 8.2.1. register_vfs in hw/pci/pcie_sriov.c mishandles the situation where a guest writes NumVFs greater than TotalVFs, leading to a buffer overflow in VF implementations. (CVE-2024-26327) An issue was discovered in QEMU 7.1.0 through 8.2.1. register_vfs in hw/pci/pcie_sriov.c does not set NumVFs to PCI_SRIOV_TOTAL_VF, and thus interaction with hw/nvme/ctrl.c is mishandled. (CVE-2024-26328) A double free vulnerability was found in QEMU virtio devices (virtio-gpu, virtio-serial-bus, virtio-crypto), where the mem_reentrancy_guard flag insufficiently protects against DMA reentrancy issues. This issue could allow a malicious privileged guest user to crash the QEMU process on the host, resulting in a denial of service or allow arbitrary code execution within the context of the QEMU process on the host. (CVE-2024-3446) A heap-based buffer overflow was found in the SDHCI device emulation of QEMU. The bug is triggered when both s->data_count and the size of s->fifo_buffer are set to 0x200, leading to an out-of-bound access. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition. (CVE-2024-3447) A flaw…

These are all security issues fixed in the qemu-8.1.2-1.1 package on the GA media of openSUSE Tumbleweed.

Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm packages provide the user-space component for running virtual machines that use KVM.

Security Fix(es):

• QEMU: e1000e: heap use-after-free in e1000e_write_packet_to_guest() (CVE-2023-3019)

• QEMU: VNC: infinite loop in inflate_buffer() leads to denial of service (CVE-2023-3255)

• QEMU: improper IDE controller reset can lead to MBR overwrite (CVE-2023-5088)

• QEMU: VNC: NULL pointer dereference in qemu_clipboard_request() (CVE-2023-6683)

• QEMU: am53c974: denial of service due to division by zero (CVE-2023-42467)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 9.4 Release Notes linked from the References section.

This update for qemu fixes the following issues:

• CVE-2023-42467: Disallow block sizes smaller than 512 (bsc#1215192).