diff options
Diffstat (limited to 'main/quagga/0003-bgpd-fix-double-free-after-extcommunity-set-BZ-799.patch')
| -rw-r--r-- | main/quagga/0003-bgpd-fix-double-free-after-extcommunity-set-BZ-799.patch | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/main/quagga/0003-bgpd-fix-double-free-after-extcommunity-set-BZ-799.patch b/main/quagga/0003-bgpd-fix-double-free-after-extcommunity-set-BZ-799.patch new file mode 100644 index 0000000000..fbd226822f --- /dev/null +++ b/main/quagga/0003-bgpd-fix-double-free-after-extcommunity-set-BZ-799.patch @@ -0,0 +1,58 @@ +From 27bf90a14670283a899b96c56dd23f8413e0973e Mon Sep 17 00:00:00 2001 +From: David Lamparter <equinox@opensourcerouting.org> +Date: Wed, 4 Jun 2014 00:59:01 +0200 +Subject: [PATCH] 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> +--- + bgpd/bgp_routemap.c | 15 ++++++++++----- + 1 file changed, 10 insertions(+), 5 deletions(-) + +diff --git a/bgpd/bgp_routemap.c b/bgpd/bgp_routemap.c +index eb5e80f..36d177d 100644 +--- a/bgpd/bgp_routemap.c ++++ b/bgpd/bgp_routemap.c +@@ -1552,14 +1552,19 @@ route_set_ecommunity (void *rule, struct prefix *prefix, + old_ecom = (bgp_attr_extra_get (bgp_info->attr))->ecommunity; + + if (old_ecom) +- new_ecom = ecommunity_merge (ecommunity_dup (old_ecom), ecom); ++ { ++ new_ecom = ecommunity_merge (ecommunity_dup (old_ecom), ecom); ++ ++ /* old_ecom->refcnt = 1 => owned elsewhere, e.g. bgp_update_receive() ++ * ->refcnt = 0 => set by a previous route-map statement */ ++ if (!old_ecom->refcnt) ++ ecommunity_free (&old_ecom); ++ } + else + new_ecom = ecommunity_dup (ecom); + +- bgp_info->attr->extra->ecommunity = ecommunity_intern (new_ecom); +- +- if (old_ecom) +- ecommunity_unintern (&old_ecom); ++ /* will be intern()'d or attr_flush()'d by bgp_update_main() */ ++ bgp_info->attr->extra->ecommunity = new_ecom; + + bgp_info->attr->flag |= ATTR_FLAG_BIT (BGP_ATTR_EXT_COMMUNITIES); + } +-- +2.0.1 + |