Commit ceaac91d authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

net: make sure we never create ifindex = 0 



Instead of allocating from 1 use proper xa_init flag,
to protect ourselves from IDs wrapping back to 0.

Fixes: 759ab1ed ("net: store netdevs in an xarray")
Reported-by: default avatarStephen Hemminger <stephen@networkplumber.org>
Link: https://lore.kernel.org/all/20230728162350.2a6d4979@hermes.local/


Reviewed-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230731171159.988962-1-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 005c9600

net/core/dev.c

+1 −2
Original line number Diff line number Diff line
@@ -11271,8 +11271,7 @@ static int __net_init netdev_init(struct net *net) 
	if (net->dev_index_head == NULL)

		goto err_idx;



	net->ifindex = 1;

	xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC);

	xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1);



	RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain);