Parsing for libxt_conntrack rev 2 is done by using rev 2's option structure, which specifies XTTYPE_PORT, and using rev 3's parser skeleton, which uses cb->nvals. Reading cb->nvals when not using XTTYPE_PORTRC (or any other multi-value type) is undefined behavior. Make it defined. Since XTTYPE_NONE is the only type that can take void, nvals logically ought to be 1. References: http://marc.info/?l=netfilter-devel&m=131370592105298&w=2 Signed-off-by: Jan Engelhardt <jengelh@xxxxxxxxxx> --- iptables/xtoptions.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/iptables/xtoptions.c b/iptables/xtoptions.c index 04344af..5f617a4 100644 --- a/iptables/xtoptions.c +++ b/iptables/xtoptions.c @@ -826,6 +826,12 @@ void xtables_option_parse(struct xt_option_call *cb) xt_params->exit_err(PARAMETER_PROBLEM, "%s: option \"--%s\" requires an argument.\n", cb->ext_name, entry->name); + /* + * Fill in fallback value for "nvals", in case an extension (as it + * happened with libxt_conntrack.2) tries to read it, despite not using + * a *RC option type. + */ + cb->nvals = 1; if (entry->type <= ARRAY_SIZE(xtopt_subparse) && xtopt_subparse[entry->type] != NULL) xtopt_subparse[entry->type](cb); -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
