From: Xin Long <lucien.xin@xxxxxxxxx>
[ Upstream commit 4f0e97d070984d487df027f163e52bb72d1713d8 ]
info->options_len is 'u8' type, and when opts_len with a value >
IP_TUNNEL_OPTS_MAX, 'info->options_len = opts_len' will cast int
to u8 and set a wrong value to info->options_len.
Kernel crashed in my test when doing:
# opts="0102:80:00800022"
# for i in {1..99}; do opts="$opts,0102:80:00800022"; done
# ip link add name geneve0 type geneve dstport 0 external
# tc qdisc add dev eth0 ingress
# tc filter add dev eth0 protocol ip parent ffff: \
flower indev eth0 ip_proto udp action tunnel_key \
set src_ip 10.0.99.192 dst_ip 10.0.99.193 \
dst_port 6081 id 11 geneve_opts $opts \
action mirred egress redirect dev geneve0
So we should do the similar check as cls_flower does, return error
when opts_len > IP_TUNNEL_OPTS_MAX in tunnel_key_copy_opts().
Fixes: 0ed5269f9e41 ("net/sched: add tunnel option support to act_tunnel_key")
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sched/act_tunnel_key.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/net/sched/act_tunnel_key.c
+++ b/net/sched/act_tunnel_key.c
@@ -135,6 +135,10 @@ static int tunnel_key_copy_opts(const st
if (opt_len < 0)
return opt_len;
opts_len += opt_len;
+ if (opts_len > IP_TUNNEL_OPTS_MAX) {
+ NL_SET_ERR_MSG(extack, "Tunnel options exceeds max size");
+ return -EINVAL;
+ }
if (dst) {
dst_len -= opt_len;
dst += opt_len;
