| Message ID | 20210411112824.1149-1-phil@philpotter.co.uk |
|---|---|
| State | New |
| Headers | show |
| Series | net: geneve: check skb is large enough for IPv4/IPv6 header | expand |
On Sun, Apr 11, 2021 at 1:28 PM Phillip Potter <phil@philpotter.co.uk> wrote: > > Check within geneve_xmit_skb/geneve6_xmit_skb that sk_buff structure > is large enough to include IPv4 or IPv6 header, and reject if not. The > geneve_xmit_skb portion and overall idea was contributed by Eric Dumazet. > Fixes a KMSAN-found uninit-value bug reported by syzbot at: > https://syzkaller.appspot.com/bug?id=abe95dc3e3e9667fc23b8d81f29ecad95c6f106f > > Suggested-by: Eric Dumazet <edumazet@google.com> > Reported-by: syzbot+2e406a9ac75bb71d4b7a@syzkaller.appspotmail.com > Signed-off-by: Phillip Potter <phil@philpotter.co.uk> Signed-off-by: Eric Dumazet <edumazet@google.com> Thanks !
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 5523f069b9a5..adfceb60f7f8 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -891,6 +891,9 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, __be16 sport; int err; + if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) + return -EINVAL; + sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true); rt = geneve_get_v4_rt(skb, dev, gs4, &fl4, info, geneve->cfg.info.key.tp_dst, sport); @@ -977,6 +980,9 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev, __be16 sport; int err; + if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr))) + return -EINVAL; + sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true); dst = geneve_get_v6_dst(skb, dev, gs6, &fl6, info, geneve->cfg.info.key.tp_dst, sport);
Check within geneve_xmit_skb/geneve6_xmit_skb that sk_buff structure is large enough to include IPv4 or IPv6 header, and reject if not. The geneve_xmit_skb portion and overall idea was contributed by Eric Dumazet. Fixes a KMSAN-found uninit-value bug reported by syzbot at: https://syzkaller.appspot.com/bug?id=abe95dc3e3e9667fc23b8d81f29ecad95c6f106f Suggested-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+2e406a9ac75bb71d4b7a@syzkaller.appspotmail.com Signed-off-by: Phillip Potter <phil@philpotter.co.uk> --- drivers/net/geneve.c | 6 ++++++ 1 file changed, 6 insertions(+)