diff options
| author | Peter Oskolkov <posk@google.com> | 2019-02-14 10:39:31 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2019-02-14 15:10:06 -0800 |
| commit | fb405883c189dd30f2fab2b3e2c954f34f000ac3 (patch) | |
| tree | 8fad4f225683a15d18682bd2e34adb3dd10b6b3c | |
| parent | 87486b23f8aa7cf55c2df4a927691c5e8540c813 (diff) | |
bpf: fix memory leak in bpf_lwt_xmit_reroute
On error the skb should be freed. Tested with diff/steps
provided by David Ahern.
v2: surface routing errors to the user instead of a generic EINVAL,
as suggested by David Ahern.
Reported-by: David Ahern <dsahern@gmail.com>
Fixes: 3bd0b15281af ("bpf: add handling of BPF_LWT_REROUTE to lwt_bpf.c")
Signed-off-by: Peter Oskolkov <posk@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | net/core/lwt_bpf.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c index 32251f3fcda0..a5c8c79d468a 100644 --- a/net/core/lwt_bpf.c +++ b/net/core/lwt_bpf.c @@ -179,17 +179,17 @@ static int bpf_lwt_xmit_reroute(struct sk_buff *skb) struct net_device *l3mdev = l3mdev_master_dev_rcu(skb_dst(skb)->dev); int oif = l3mdev ? l3mdev->ifindex : 0; struct dst_entry *dst = NULL; + int err = -EAFNOSUPPORT; struct sock *sk; struct net *net; bool ipv4; - int err; if (skb->protocol == htons(ETH_P_IP)) ipv4 = true; else if (skb->protocol == htons(ETH_P_IPV6)) ipv4 = false; else - return -EAFNOSUPPORT; + goto err; sk = sk_to_full_sk(skb->sk); if (sk) { @@ -215,8 +215,10 @@ static int bpf_lwt_xmit_reroute(struct sk_buff *skb) fl4.saddr = iph->saddr; rt = ip_route_output_key(net, &fl4); - if (IS_ERR(rt)) - return -EINVAL; + if (IS_ERR(rt)) { + err = PTR_ERR(rt); + goto err; + } dst = &rt->dst; } else { struct ipv6hdr *iph6 = ipv6_hdr(skb); @@ -231,12 +233,17 @@ static int bpf_lwt_xmit_reroute(struct sk_buff *skb) fl6.saddr = iph6->saddr; err = ipv6_stub->ipv6_dst_lookup(net, skb->sk, &dst, &fl6); - if (err || IS_ERR(dst)) - return -EINVAL; + if (unlikely(err)) + goto err; + if (IS_ERR(dst)) { + err = PTR_ERR(dst); + goto err; + } } if (unlikely(dst->error)) { + err = dst->error; dst_release(dst); - return -EINVAL; + goto err; } /* Although skb header was reserved in bpf_lwt_push_ip_encap(), it @@ -246,17 +253,21 @@ static int bpf_lwt_xmit_reroute(struct sk_buff *skb) */ err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev)); if (unlikely(err)) - return err; + goto err; skb_dst_drop(skb); skb_dst_set(skb, dst); err = dst_output(dev_net(skb_dst(skb)->dev), skb->sk, skb); if (unlikely(err)) - return err; + goto err; /* ip[6]_finish_output2 understand LWTUNNEL_XMIT_DONE */ return LWTUNNEL_XMIT_DONE; + +err: + kfree_skb(skb); + return err; } static int bpf_xmit(struct sk_buff *skb) |