diff options
author | Willem de Bruijn <willemb@google.com> | 2016-03-09 21:58:33 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:45:10 +0900 |
commit | d4d1bf367516520e863ab170f24ed6ba3da8b7ba (patch) | |
tree | c32d8a7bb7a8309c750e3ce3870cbf9b813a5339 /net | |
parent | 6804052fa9d86e9a512c88b24a5debbfc1a490fc (diff) |
ax25: add link layer header validation function
[ Upstream commit ea47781c26510e5d97f80f9aceafe9065bd5e3aa ]
As variable length protocol, AX25 fails link layer header validation
tests based on a minimum length. header_ops.validate allows protocols
to validate headers that are shorter than hard_header_len. Implement
this callback for AX25.
See also http://comments.gmane.org/gmane.linux.network/401064
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
-rw-r--r-- | net/ax25/ax25_ip.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c index b563a3f5f2a8..2fa3be965101 100644 --- a/net/ax25/ax25_ip.c +++ b/net/ax25/ax25_ip.c @@ -228,8 +228,23 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb) } #endif +static bool ax25_validate_header(const char *header, unsigned int len) +{ + ax25_digi digi; + + if (!len) + return false; + + if (header[0]) + return true; + + return ax25_addr_parse(header + 1, len - 1, NULL, NULL, &digi, NULL, + NULL); +} + const struct header_ops ax25_header_ops = { .create = ax25_hard_header, + .validate = ax25_validate_header, }; EXPORT_SYMBOL(ax25_header_ops); |