CVE-2023-52778

/// Technical description

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

mptcp: deal with large GSO size

After the blamed commit below, the TCP sockets (and the MPTCP subflows)

can build egress packets larger than 64K. That exceeds the maximum DSS

data size, the length being misrepresent on the wire and the stream being

corrupted, as later observed on the receiver:

WARNING: CPU: 0 PID: 9696 at net/mptcp/protocol.c:705 __mptcp_move_skbs_from_subflow+0x2604/0x26e0

CPU: 0 PID: 9696 Comm: syz-executor.7 Not tainted 6.6.0-rc5-gcd8bdf563d46 #45

Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014

netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'.

RIP: 0010:__mptcp_move_skbs_from_subflow+0x2604/0x26e0 net/mptcp/protocol.c:705

RSP: 0018:ffffc90000006e80 EFLAGS: 00010246

RAX: ffffffff83e9f674 RBX: ffff88802f45d870 RCX: ffff888102ad0000

netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'.

RDX:

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References