CVE-2024-56648

/// Technical description

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

net: hsr: avoid potential out-of-bound access in fill_frame_info()

syzbot is able to feed a packet with 14 bytes, pretending

it is a vlan one.

Since fill_frame_info() is relying on skb->mac_len already,

extend the check to cover this case.

BUG: KMSAN: uninit-value in fill_frame_info net/hsr/hsr_forward.c:709 [inline]

BUG: KMSAN: uninit-value in hsr_forward_skb+0x9ee/0x3b10 net/hsr/hsr_forward.c:724

fill_frame_info net/hsr/hsr_forward.c:709 [inline]

hsr_forward_skb+0x9ee/0x3b10 net/hsr/hsr_forward.c:724

hsr_dev_xmit+0x2f0/0x350 net/hsr/hsr_device.c:235

__netdev_start_xmit include/linux/netdevice.h:5002 [inline]

netdev_start_xmit include/linux/netdevice.h:5011 [inline]

xmit_one net/core/dev.c:3590 [inline]

dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3606

__dev_queue_xmit+0x366a/0x57d0 net/core/dev.c:4434

dev_queue_xmit include/linux/netdevice.h:3168 [inline]

packet_xmit+0x9c/0x6c0 net/packet/a

/// 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