commit c3f63d70f236bb7685e6d11d1d9b5b351552e600 Author: Greg Kroah-Hartman Date: Fri Nov 6 13:17:37 2026 -0500 Linux 6.18.62 Signed-off-by: Greg Kroah-Hartman commit c49934da934cf495faf782aa5d84f413221c9be6 Author: Juergen Gross Date: Thu Nov 5 08:27:38 2026 +0100 xen-blkback: Avoid UAF when reading I/O statistics commit a02926f7c89bfc798ee9514e09694ff4279928a1 upstream. Reading I/O statistics via sysfs concurrently with tearing down a frontend device might result in UAF or a NULL dereference, as the reading of the statistics data is not synchronized with freeing the data. Use a rwlock for synchronizing. This is XSA-528 / CVE-2026-100082 Reported-by: Yehyeong Lee Signed-off-by: Juergen Gross Acked-by: Roger Pau Monné Signed-off-by: Greg Kroah-Hartman commit 34f0f63dc6dc11895a17bb5672451b6b11622c99 Author: Jan Beulich Date: Fri Nov 6 17:07:01 2026 +0100 xen-netback: defer xenvif_mcast_addr_list_free() commit bfddc420afe827d9f06458cdf8087cd602f8c9cb upstream. In order for the function to legitimately avoid locking/RCU, it needs to run after all TX/RX processing has finished/stopped: Lookups happen from xenvif_start_xmit(), while adds/removes happen from xenvif_tx_action() (called out of xenvif_poll()). Move the call out of xenvif_disconnect_data() (the call to the function from connect()'s error path doesn't require any cleaning up there), and put it past the synchronization point in backend_disconnect(). This is XSA-527 / CVE-2026-100081. Fixes: b17075d5c198 ("xen-netback: fix race condition on XenBus disconnect") Reported-by: kerhunt Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman commit 37d5a73170579b30e67cc8b19ec69715eea3a6b6 Author: Juergen Gross Date: Fri Nov 6 13:07:52 2026 +0100 xen-netback: Fix UAF when reading statistics data commit 5fb756f1bbec7a3862dda5d79028bf656271804c upstream. The network statistic data in the driver is protected by RCU. Unfortunately when tearing down the queues after an error during connecting to the frontend (e.g. due to illegal Xenstore data filled in by the guest), the statistic data is being freed without synchronizing the RCU state. In case the data is being read via sysfs in this phase, access to already freed memory or memory being in new use is possible. Fix that by calling synchronize_net() before freeing the queue data. This is XSA-526 / CVE-2026-100080 Reported-by: Yehyeong Lee Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman