CVE-2024-35944 — VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()

Affected: Linux, Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved:

VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()

Syzkaller hit 'WARNING in dg_dispatch_as_host' bug.

memcpy: detected field-spanning write (size 56) of single field "&dg_info->msg" at drivers/misc/vmw_vmci/vmci_datagram.c:237 (size 24)

WARNING: CPU: 0 PID: 1555 at drivers/misc/vmw_vmci/vmci_datagram.c:237 dg_dispatch_as_host+0x88e/0xa60 drivers/misc/vmw_vmci/vmci_datagram.c:237

Some code commentry, based on my understanding:

544 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size) /// This is 24 + payload_size

memcpy(&dg_info->msg, dg, dg_size); Destination = dg_info->msg ---> this is a 24 byte structure(struct vmci_datagram) Source = dg --> this is a 24 byte structure (struct vmci_datagram) Size = dg_size = 24 + payload_size

{payload_size = 56-24 =32} -- Syzkaller managed to set payload_size to 32.

35 struct delayed_datagram_info { 36 struct datagram_entry *entry; 37 struct work_struct work; 38 bool in_dg_host_queue; 39 /* msg and msg_payload must be together. */ 40 struct vmci_datagram msg; 41 u8 msg_payload[]; 42 };

So those extra bytes of payload are copied into msg_payload[], a run time warning is seen while fuzzing with Syzkaller.

One possible way to fix the warning is to split the memcpy() into two parts -- one -- direct assignment of msg and second taking care of payload.

Gustavo quoted: "U…

USN-6893-1 — linux, linux-azure, linux-gcp, linux-ibm, linux-intel, linux-lowlatency, linux-oem-6.8, linux-raspi vulnerabilities

Affected: Ubuntu:24.04:LTS: linux, Ubuntu:24.04:LTS: linux-azure, Ubuntu:24.04:LTS: linux-gcp, Ubuntu:24.04:LTS: linux-ibm, Ubuntu:24.04:LTS: linux-intel, Ubuntu:24.04:LTS: linux-lowlatency, Ubuntu:24.04:LTS: linux-oem-6.8, Ubuntu:24.04:LTS: linux-raspi

It was discovered that a race condition existed in the Bluetooth subsystem in the Linux kernel when modifying certain settings values through debugfs. A privileged local attacker could use this to cause a denial of service. (CVE-2024-24857, CVE-2024-24858, CVE-2024-24859)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - RISC-V architecture; - S390 architecture; - x86 architecture; - Block layer subsystem; - Compute Acceleration Framework; - Accessibility subsystem; - Android drivers; - Drivers core; - Bluetooth drivers; - Clock framework and drivers; - Data acquisition framework and drivers; - Cryptographic API; - Buffer Sharing and Synchronization framework; - GPU drivers; - On-Chip Interconnect management framework; - IOMMU subsystem; - Multiple devices driver; - Media drivers; - VMware VMCI Driver; - Network drivers; - Microsoft Azure Network Adapter (MANA) driver; - Device tree and open firmware driver; - Chrome hardware platform drivers; - i.MX PM domains; - TI SCI PM domains driver; - S/390 drivers; - SCSI drivers; - SPI subsystem; - Thermal drivers; - TTY drivers; - USB subsystem; - Framebuffer layer; - BTRFS file system; - Network file system server daemon; - NILFS2 file system; - File systems infrastructure; - Pstore file system; - SMB…

Most recent entries from all

CVE-2024-35944 — VMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()

USN-6893-1 — linux, linux-azure, linux-gcp, linux-ibm, linux-intel, linux-lowlatency, linux-oem-6.8, linux-raspi vulnerabilities