diff options
| author | Maoyi Xie <maoyixie.tju@gmail.com> | 2026-06-12 16:59:37 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-06-17 16:01:52 -0700 |
| commit | 95cceadbfd52d7239bd730afdda0655287d77425 (patch) | |
| tree | 2732e0e3314be4532e8160682407376b1d5a532a /net | |
| parent | 8211a26324667980a463c069469a818e71207e02 (diff) | |
| download | ath-95cceadbfd52d7239bd730afdda0655287d77425.tar.gz | |
net: ip_vti: require CAP_NET_ADMIN in the device netns for changelink
vti_changelink() operates on at most two netns, dev_net(dev) and the
tunnel link netns t->net. They differ once the device is created in or
moved to a netns other than the one the request runs in. The rtnl
changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a
caller privileged there but not in t->net can rewrite a tunnel that
lives in t->net.
Gate vti_changelink() on rtnl_dev_link_net_capable() at its top,
before any attribute is parsed.
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCOSzP1vaThGV35_VnsRCb=87_CPjPVsTHbq905k8A+BuUg@mail.gmail.com/
Fixes: 895de9a3488a ("vti4: Enable namespace changing")
Cc: stable@vger.kernel.org
Signed-off-by: Maoyi Xie <maoyixie.tju@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260612085941.3158249-4-maoyixie.tju@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ip_vti.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c index 95b6bb78fcd27..3b80929994a00 100644 --- a/net/ipv4/ip_vti.c +++ b/net/ipv4/ip_vti.c @@ -596,6 +596,9 @@ static int vti_changelink(struct net_device *dev, struct nlattr *tb[], struct ip_tunnel_parm_kern p; __u32 fwmark = t->fwmark; + if (!rtnl_dev_link_net_capable(dev, t->net)) + return -EPERM; + vti_netlink_parms(data, &p, &fwmark); return ip_tunnel_changelink(dev, tb, &p, fwmark); } |