mnl: check for NLM_F_DUMP_INTR when dumping object lists

This flag allows to detect that an update has ocurred while dumping
any of the object lists. In case of interference, nft cancels the
netlink socket to skip processing the remaining stale entries and
it retries to obtain fresh list of objects.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/src/main.c b/src/main.c
index a446bc68..30ea2c6c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -223,8 +223,14 @@ int nft_run(void *scanner, struct parser_state *state, struct list_head *msgs)
 	ret = nft_parse(scanner, state);
 	if (ret != 0 || state->nerrs > 0)
 		return -1;
+retry:
+	ret = nft_netlink(state, msgs);
+	if (ret < 0 && errno == EINTR) {
+		netlink_restart();
+		goto retry;
+	}
 
-	return nft_netlink(state, msgs);
+	return ret;
 }
 
 int main(int argc, char * const *argv)