tree e52498c5d70f6efef4d9a827b6974a2f597b2e30
parent 73d78ea0153fd36a300be5fec2ef0fca34a67477
author David Lamparter <equinox@opensourcerouting.org> 1401836341 +0200
committer David Lamparter <equinox@opensourcerouting.org> 1404038841 +0200

bgpd: fix double free after extcommunity set (BZ#799)

The route-map extcommunity set code was incorrectly assuming that it
owns the intern'd struct ecommunity reference.  In reality, the intern'd
reference belongs to bgp_update_receive() and we're not supposed to
touch it in the route-map code.

Instead, like all the other set commands, we use a on-heap but
non-intern'd ecommunity to set the new value.  This is then either
intern'd in bgp_update_main/_rsclient() through bgp_attr_intern(), or
free'd through bgp_attr_flush().

This fixes Bugzilla #799, which is that bgpd otherwise crashes with a
double free.  The ecommunity got unintern'd first in the route-map set
command, then in bgp_update_receive().

Debugged-by: Milan Kocian <milon@wq.cz>
Reported-by: Florian S <florian@herrenlohe.de>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>