lkml.org 
[lkml]   [2019]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.19 142/306] bpf: devmap: fix wrong interface selection in notifier_call
Date
From: Taehee Yoo <ap420073@gmail.com>

[ Upstream commit f592f804831f1cf9d1f9966f58c80f150e6829b5 ]

The dev_map_notification() removes interface in devmap if
unregistering interface's ifindex is same.
But only checking ifindex is not enough because other netns can have
same ifindex. so that wrong interface selection could occurred.
Hence netdev pointer comparison code is added.

v2: compare netdev pointer instead of using net_eq() (Daniel Borkmann)
v1: Initial patch

Fixes: 2ddf71e23cc2 ("net: add notifier hooks for devmap bpf map")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/bpf/devmap.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index fc500ca464d00..1defea4b27553 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -520,8 +520,7 @@ static int dev_map_notification(struct notifier_block *notifier,
struct bpf_dtab_netdev *dev, *odev;

dev = READ_ONCE(dtab->netdev_map[i]);
- if (!dev ||
- dev->dev->ifindex != netdev->ifindex)
+ if (!dev || netdev != dev->dev)
continue;
odev = cmpxchg(&dtab->netdev_map[i], dev, NULL);
if (dev == odev)
--
2.20.1


\
 
 \ /
  Last update: 2019-11-27 22:25    [W:0.786 / U:2.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site