diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-11-10 13:12:35 -0800 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-04-11 10:58:37 +0200 |
| commit | 9f8215f02033a28b08a85aa1f4679901bb1fe21b (patch) | |
| tree | 1ae14c1bc0a2b3f618e3620580a29cde94aed39f /include/linux | |
| parent | 71f4c31adf71752a25db9faeec577cfabad45b78 (diff) | |
tcp: take care of truncations done by sk_filter()
commit ac6e780070e30e4c35bd395acfe9191e6268bdd3 upstream.
With syzkaller help, Marco Grassi found a bug in TCP stack,
crashing in tcp_collapse()
Root cause is that sk_filter() can truncate the incoming skb,
but TCP stack was not really expecting this to happen.
It probably was expecting a simple DROP or ACCEPT behavior.
We first need to make sure no part of TCP header could be removed.
Then we need to adjust TCP_SKB_CB(skb)->end_seq
Many thanks to syzkaller team and Marco for giving us a reproducer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Marco Grassi <marco.gra@gmail.com>
Reported-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/filter.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index f65f5a69d..c2bea01d0 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -36,7 +36,11 @@ static inline unsigned int sk_filter_len(const struct sk_filter *fp) return fp->len * sizeof(struct sock_filter) + sizeof(*fp); } -extern int sk_filter(struct sock *sk, struct sk_buff *skb); +int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); +static inline int sk_filter(struct sock *sk, struct sk_buff *skb) +{ + return sk_filter_trim_cap(sk, skb, 1); +} extern unsigned int sk_run_filter(const struct sk_buff *skb, const struct sock_filter *filter); extern int sk_unattached_filter_create(struct sk_filter **pfp, |