system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-10-04 02:10:58 +00:00
Code Issues Packages Projects Releases Wiki Activity

bpf: Fix dev pointer dereference from sk_skb

Browse source 
Dan Carpenter reports:

The patch 6acc9b432e: "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>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Joe Stringer 2018-10-12 14:50:53 -07:00 committed by Alexei Starovoitov
parent 1ae80cf319
commit 67e89ac328
1 changed files with 4 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
net/core/filter.c
View file

@ -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;