src: Fix nftnl_*_get_data() to return the real attribute length

All getters must set the memory size of the attributes, ie. this
includes the nul-termination in strings.

For references to opaque objects hidden behind the curtain, report
a zero size.

Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/expr.c b/src/expr.c
index f802725..e5c1dd3 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -119,6 +119,7 @@ const void *nftnl_expr_get(const struct nftnl_expr *expr,
 
 	switch(type) {
 	case NFTNL_EXPR_NAME:
+		*data_len = strlen(expr->ops->name) + 1;
 		ret = expr->ops->name;
 		break;
 	default: