diff options
| author | Willem de Bruijn <willemb@google.com> | 2016-07-12 18:18:56 -0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-07-13 11:53:40 -0700 |
| commit | f4979fcea7fd36d8e2f556abef86f80e0d5af1ba (patch) | |
| tree | e44115be36c8eef0769d4defe66168635c64137a /include/linux/filter.h | |
| parent | 22cb99fb76fb56b38f59770fbf22be03bb796d8d (diff) | |
rose: limit sk_filter trim to payload
Sockets can have a filter program attached that drops or trims
incoming packets based on the filter program return value.
Rose requires data packets to have at least ROSE_MIN_LEN bytes. It
verifies this on arrival in rose_route_frame and unconditionally pulls
the bytes in rose_recvmsg. The filter can trim packets to below this
value in-between, causing pull to fail, leaving the partial header at
the time of skb_copy_datagram_msg.
Place a lower bound on the size to which sk_filter may trim packets
by introducing sk_filter_trim_cap and call this for rose packets.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/filter.h')
| -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 6fc31ef1da2d..8f74f3d61894 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -467,7 +467,11 @@ 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); +} struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); void bpf_prog_free(struct bpf_prog *fp); |