Re: [PATCH v1 net 1/3] gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().
From: Simon Horman <horms@kernel.org>
Date: 2025-01-08 10:40:44
On Wed, Jan 08, 2025 at 03:28:32PM +0900, Kuniyuki Iwashima wrote:
gtp_newlink() links the gtp device to a list in dev_net(dev).
However, even after the gtp device is moved to another netns,
it stays on the list but should be invisible.
Let's use for_each_netdev_rcu() for netdev traversal in
gtp_genl_dump_pdp().
Note that gtp_dev_list is no longer used under RCU, so list
helpers are converted to the non-RCU variant.
Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Reported-by: Xiao Liang <redacted>
Closes: https://lore.kernel.org/netdev/CABAhCOQdBL6h9M2C+kd+bGivRJ9Q72JUxW+-gur0nub_=PmFPA@mail.gmail.com/ (local)
Signed-off-by: Kuniyuki Iwashima <redacted>
---
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Harald Welte <laforge@gnumonks.org>...
quoted hunk ↗ jump to hunk
@@ -2280,7 +2281,10 @@ static int gtp_genl_dump_pdp(struct sk_buff *skb, return 0; rcu_read_lock(); - list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) { + for_each_netdev_rcu(net, dev) { + if (dev->rtnl_link_ops != >p_link_ops) + continue; + if (last_gtp && last_gtp != gtp) continue; else
Hi Iwashima-san, With this change gtp seems to be uninitialised here. And, also, it looks like gn is now set but otherwise unused in this function. Flagged by W=1 builds with clang-19. ...