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/gen.c b/src/gen.c
index 37a9049..c69d2f8 100644
--- a/src/gen.c
+++ b/src/gen.c
@@ -100,6 +100,7 @@ const void *nftnl_gen_get_data(const struct nftnl_gen *gen, uint16_t attr,
 
 	switch(attr) {
 	case NFTNL_GEN_ID:
+		*data_len = sizeof(gen->id);
 		return &gen->id;
 	}
 	return NULL;