diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2023-08-18 18:26:02 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-08-20 11:40:03 +0100 |
| commit | f534f6581ec084fe94d6759f7672bd009794b07e (patch) | |
| tree | 8b9f5a61ebd147d1bab4f432e4a9eabdee545338 /drivers/net/veth.c | |
| parent | c727c6f788e673add829e4b54e7894fb2907df1c (diff) | |
net: validate veth and vxcan peer ifindexes
veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.
Using iproute2 with user-space-level checking removed:
Before:
# ./ip link add index 10 type veth peer index -1
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
10: veth1@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
-1: veth0@veth1: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff
Now:
$ ./ip link add index 10 type veth peer index -1
Error: ifindex can't be negative.
This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.
Fixes: e6f8f1a739b6 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/veth.c')
| -rw-r--r-- | drivers/net/veth.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 509e901da41d..ef8eacb596f7 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -1861,10 +1861,7 @@ static int veth_newlink(struct net *src_net, struct net_device *dev, nla_peer = data[VETH_INFO_PEER]; ifmp = nla_data(nla_peer); - err = rtnl_nla_parse_ifla(peer_tb, - nla_data(nla_peer) + sizeof(struct ifinfomsg), - nla_len(nla_peer) - sizeof(struct ifinfomsg), - NULL); + err = rtnl_nla_parse_ifinfomsg(peer_tb, nla_peer, extack); if (err < 0) return err; |