CVE-2026-97955

/// Technical description

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

net: mana: restore the XDP program pointer when pre-allocation fails

mana_xdp_set() publishes the new program into apc->bpf_prog before it

allocates anything, because mana_pre_alloc_rxbufs() sizes the buffers

from it via mana_get_rxbuf_cfg(). When that allocation fails the

function returns the error directly, skipping the err_dealloc_rxbuffs

label which is the only place that restores the previous pointer.

The attach is reported as failed, so the BPF core drops the reference it

held for the caller and the program can be freed, while apc->bpf_prog

still points at it. The next consumer of mana_xdp_get() - typically

mana_chn_setxdp() from mana_alloc_queues() on the following ifup, or

after a TX timeout reset - then calls bpf_prog_add() on freed memory.

This is reachable from an ordinary "ip link set dev ethX xdp obj ..."

whenever the per-queue RX buffer pre-allocation cannot be satisfied.

Restore the previous program

/// 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