Medium [CVE-2026-53216] limit XDP frame size to the RX buffer

In the Linux kernel, the following vulnerability has been resolved: net: mvpp2: limit XDP frame size to the RX buffer mvpp2 has short and long BM pools, and short pool buffers can be smaller than PAGE_SIZE. The XDP path nevertheless initializes every xdp_buff with PAGE_SIZE as frame size.

XDP helpers use frame_sz to validate tail growth and to derive the hard end of the data area. Advertising PAGE_SIZE for short buffers can let bpf_xdp_adjust_tail() grow a packet past the real allocation, corrupting memory or later tripping skb tailroom checks.

Initialize the XDP buffer with bm_pool->frag_size so XDP tailroom matches the actual buffer backing the packet. A flaw was found in the Linux kernel's mvpp2 network driver.

This vulnerability arises from improper handling of the eXpress Data Path (XDP) frame size, where the system advertises a larger frame size than the actual allocated buffer for short buffer pools. This can allow the bpf_xdp_adjust_tail() function to write data beyond the intended memory boundary, leading to memory corruption.

Such corruption could potentially result in system instability or denial of service. Red Hat severity: Moderate.

Weakness: CWE-787. Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected.