diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-11-10 13:12:35 -0800 |
|---|---|---|
| committer | Willy Tarreau <w@1wt.eu> | 2017-02-10 11:03:46 +0100 |
| commit | 56325d9fb7b138b228577ae99382b70084ab82f3 (patch) | |
| tree | 3501ed6f8a4a985b631713661efc41ad043f2bad /include | |
| parent | d318f82f1c4e3823253fcc9dc2053a46ef7b14a6 (diff) | |
| download | linux-56325d9fb7b138b228577ae99382b70084ab82f3.tar.gz linux-56325d9fb7b138b228577ae99382b70084ab82f3.tar.bz2 linux-56325d9fb7b138b228577ae99382b70084ab82f3.zip | |
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')
| -rw-r--r-- | include/linux/filter.h | 6 | ||||
| -rw-r--r-- | include/net/tcp.h | 1 |
2 files changed, 6 insertions, 1 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index f65f5a69db8f..c2bea01d0466 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, diff --git a/include/net/tcp.h b/include/net/tcp.h index 1c5e037f78d1..79cd118d5994 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1029,6 +1029,7 @@ static inline void tcp_prequeue_init(struct tcp_sock *tp) } extern bool tcp_prequeue(struct sock *sk, struct sk_buff *skb); +int tcp_filter(struct sock *sk, struct sk_buff *skb); #undef STATE_TRACE |