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

Summary

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 on that error path.

Timeline

1. Sep 25, 2026, 10:23 AM UTCCVE published
2. Oct 19, 2026, 9:11 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 730ff06d3f5cc2ce0348414b78c10528b767d4a3 · fixed in 5b3cdc9abd82b7e49e0f1a21d6eb75466c5ecef8; From 730ff06d3f5cc2ce0348414b78c10528b767d4a3 · fixed in 9801edfba8dfcdb1da3b0afccdf143e13d646b56; From 730ff06d3f5cc2ce0348414b78c10528b767d4a3 · fixed in 4c46beb807efcc93f5899ebe1f5958248eb296c6

• Linux Linux

  6.18

• KernelLinux

  From 6.18.0 · fixed in 6.18.53; From 6.19.0 · fixed in 7.2.7

References 3