diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-11-10 13:12:35 -0800 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2016-11-28 22:22:40 +0100 |
| commit | 9edbcfdced9628dfdc6dc54d625e571aef81a8a5 (patch) | |
| tree | 65f1b9547d2aba0f6351ee78e6d4136ddf3b143c /include | |
| parent | 75ed3f35930e79bcb1a5e61d0520953fea3e30a2 (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: Jiri Slaby <jslaby@suse.cz>
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 ff4e40cd45b1..264c1a440240 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -41,7 +41,11 @@ static inline unsigned int sk_filter_size(unsigned int proglen) offsetof(struct sk_filter, insns[proglen])); } -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 035135b43820..83d03f86e914 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1049,6 +1049,7 @@ 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 |