diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-11-10 13:12:35 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-11-21 10:06:40 +0100 |
| commit | 225a24ae97331f3b9d97c1bb97b1e30b3633bcf4 (patch) | |
| tree | 717348befe9ab3ccc232de9ba1d105f15e19b9b9 /include | |
| parent | ae9e052a58ef2357e4b7543901af8f6daf91a0f7 (diff) | |
tcp: take care of truncations done by sk_filter()
[ Upstream commit ac6e780070e30e4c35bd395acfe9191e6268bdd3 ]
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 5110d4211866..ccb98b459c59 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -421,7 +421,11 @@ static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) } #endif /* CONFIG_DEBUG_SET_MODULE_RONX */ -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); +} int bpf_prog_select_runtime(struct bpf_prog *fp); void bpf_prog_free(struct bpf_prog *fp); diff --git a/include/net/tcp.h b/include/net/tcp.h index 9c3ab544d3a8..e9d7a8ef9a6d 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1156,6 +1156,7 @@ static inline void tcp_prequeue_init(struct tcp_sock *tp) } bool tcp_prequeue(struct sock *sk, struct sk_buff *skb); +int tcp_filter(struct sock *sk, struct sk_buff *skb); #undef STATE_TRACE |