tree 926c7ad1ecbaa21c070c4ef0c3e9092843963027
parent 68c7b36f637c5d9a05b32b2868e44ea838f83f78
author Willy Tarreau <w@1wt.eu> 1634243438 +0200
committer Willy Tarreau <w@1wt.eu> 1634747272 +0200
encoding latin1

BUG/MEDIUM: resolvers: use correct storage for the target address

The struct resolv_answer_item contains an address field of type
"sockaddr" which is only 16 bytes long, but which is used to store
either IPv4 or IPv6. Fortunately, the contents only overlap with
the "target" field that follows it and that is large enough to
absorb the extra bytes needed to store AAAA records. But this is
dangerous as just moving fields around could result in memory
corruption.

The fix uses a union and removes the casts that were used to hide
the problem.

Older versions need to be checked and possibly fixed. This needs
to be backported anyway.

(cherry picked from commit b4ca0195a9591614bfcebe9b7fe80c1ce9f94d8d)
Signed-off-by: Willy Tarreau <w@1wt.eu>