| Message ID | 20181012215053.17830-1-joe@wand.net.nz |
|---|---|
| State | Accepted, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next] bpf: Fix dev pointer dereference from sk_skb | expand |
On Fri, Oct 12, 2018 at 02:50:53PM -0700, Joe Stringer wrote: > Dan Carpenter reports: > > The patch 6acc9b432e67: "bpf: Add helper to retrieve socket in BPF" > from Oct 2, 2018, leads to the following Smatch complaint: > > net/core/filter.c:4893 bpf_sk_lookup() > error: we previously assumed 'skb->dev' could be null (see line 4885) > > Fix this issue by checking skb->dev before using it. > > Signed-off-by: Joe Stringer <joe@wand.net.nz> Applied, Thanks
diff --git a/net/core/filter.c b/net/core/filter.c index 4bbc6567fcb8..b844761b5d4c 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4821,9 +4821,12 @@ static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = { static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple, struct sk_buff *skb, u8 family, u8 proto) { - int dif = skb->dev->ifindex; bool refcounted = false; struct sock *sk = NULL; + int dif = 0; + + if (skb->dev) + dif = skb->dev->ifindex; if (family == AF_INET) { __be32 src4 = tuple->ipv4.saddr;
Dan Carpenter reports: The patch 6acc9b432e67: "bpf: Add helper to retrieve socket in BPF" from Oct 2, 2018, leads to the following Smatch complaint: net/core/filter.c:4893 bpf_sk_lookup() error: we previously assumed 'skb->dev' could be null (see line 4885) Fix this issue by checking skb->dev before using it. Signed-off-by: Joe Stringer <joe@wand.net.nz> --- net/core/filter.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)