diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-06-13 05:31:32 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-06-13 07:58:49 +0300 |
| commit | 1e98a0f08abddde87f0f93237f10629ecb4880ef (patch) | |
| tree | d076e4b8b38b5cc82e865986ceb736585dca2374 | |
| parent | 5b173cf92729b02ff8207abd85bfcbbef3443b94 (diff) | |
| download | linux-1e98a0f08abddde87f0f93237f10629ecb4880ef.tar.xz | |
flow_dissector: fix ipv6 dst, hop-by-hop and routing ext hdrs
__skb_header_pointer() returns a pointer that must be checked.
Fixes infinite loop reported by Alexei, and add __must_check to
catch these errors earlier.
Fixes: 6a74fcf426f5 ("flow_dissector: add support for dst, hop-by-hop and routing ext hdrs")
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Tested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/skbuff.h | 9 | ||||
| -rw-r--r-- | net/core/flow_dissector.c | 6 |
2 files changed, 9 insertions, 6 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cc612fc0a894..a7acc92aa668 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2743,8 +2743,9 @@ __wsum __skb_checksum(const struct sk_buff *skb, int offset, int len, __wsum skb_checksum(const struct sk_buff *skb, int offset, int len, __wsum csum); -static inline void *__skb_header_pointer(const struct sk_buff *skb, int offset, - int len, void *data, int hlen, void *buffer) +static inline void * __must_check +__skb_header_pointer(const struct sk_buff *skb, int offset, + int len, void *data, int hlen, void *buffer) { if (hlen - offset >= len) return data + offset; @@ -2756,8 +2757,8 @@ static inline void *__skb_header_pointer(const struct sk_buff *skb, int offset, return buffer; } -static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, - int len, void *buffer) +static inline void * __must_check +skb_header_pointer(const struct sk_buff *skb, int offset, int len, void *buffer) { return __skb_header_pointer(skb, offset, len, skb->data, skb_headlen(skb), buffer); diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 22e4dffa0c8b..476e5dda59e1 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -394,9 +394,11 @@ ip_proto_again: opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr), data, hlen, &_opthdr); + if (!opthdr) + return false; - ip_proto = _opthdr[0]; - nhoff += (_opthdr[1] + 1) << 3; + ip_proto = opthdr[0]; + nhoff += (opthdr[1] + 1) << 3; goto ip_proto_again; } |