David Lee 50aff80475 net/packet: avoid fanout hook re-registration after unregister ... packet_set_ring() temporarily detaches a socket from packet delivery while reconfiguring its ring. It records the previous running state, clears po->num, unregisters the protocol hook when needed, drops po->bind_lock, and later restores po->num and re-registers the hook from the saved was_running value. That unlocked window can race with NETDEV_UNREGISTER. The notifier can observe the socket as not running, skip __unregister_prot_hook(), and invalidate the per-socket binding by setting po->ifindex to -1 and clearing po->prot_hook.dev. A one-member fanout group can still retain its shared fanout hook device pointer. When packet_set_ring() resumes, re-registering solely from the stale was_running state can re-add the fanout hook after the device has been unregistered. Treat po->ifindex == -1 as an invalidated binding after reacquiring po->bind_lock. This is distinct from ifindex 0, the normal unbound/wildcard state: ifindex -1 marks an existing device binding that was invalidated when the device was unregistered. Restore po->num as before, but do not re-register the hook if device unregister already detached the socket. Fixes: dc99f60069 ("packet: Add fanout support.") Link: https://lore.kernel.org/netdev/20260701113947.23180-1-david.lee@trailofbits.com/ Signed-off-by: David Lee <david.lee@trailofbits.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260707104440.833129-1-david.lee@trailofbits.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2026-07-20 18:15:20 -07:00
..
af_packet.c	net/packet: avoid fanout hook re-registration after unregister	2026-07-20 18:15:20 -07:00
diag.c	net: change sock.sk_ino and sock_i_ino() to u64	2026-03-06 14:31:26 +01:00
internal.h	net: af_packet: Use hrtimer to do the retire operation	2025-09-11 18:40:06 -07:00
Kconfig	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
Makefile