BUG/MEDIUM: connection: sanitize PPv2 header length before parsing address information

Previously, if hdr_v2->len was less than the length of the protocol
specific address information we could have read after the end of the
buffer and initialize the sockaddr structure with junk.

Signed-off-by: KOVACS Krisztian <hidden@balabit.com>

[WT: this is only tagged medium since proxy protocol is only used from
 trusted sources]

This must be backported to 1.5.
(cherry picked from commit efd3aa93412648cf923bf3d2e171c0b84e9d7a69)
1 file changed