[PATCH 01/12] batctl: handle netlink callback object on error

The libnl callback object is allocated and must be deallocated when it is
no longer used. This is especially important when an error happened.

Fixes: d8dd1ff1a0fe ("batctl: Use netlink to replace some of debugfs")
Fixes: f109b3473f86 ("batctl: introduce throughput meter support")
Signed-off-by: Sven Eckelmann <[email protected]>
---
 netlink.c         |  6 +++++-
 routing_algo.c    |  1 +
 throughputmeter.c | 10 +++++++++-
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/netlink.c b/netlink.c
index 46fb993..4a3ab60 100644
--- a/netlink.c
+++ b/netlink.c
@@ -489,11 +489,15 @@ char *netlink_get_info(struct state *state, uint8_t nl_cmd, const char *header)
 	nl_cb_err(cb, NL_CB_CUSTOM, netlink_print_error, NULL);
 
 	ret = nl_recvmsgs(state->sock, cb);
-	if (ret < 0)
+	if (ret < 0) {
+		nl_cb_put(cb);
 		return opts.remaining_header;
+	}
 
 	nl_wait_for_ack(state->sock);
 
+	nl_cb_put(cb);
+
 	return opts.remaining_header;
 }
 
diff --git a/routing_algo.c b/routing_algo.c
index 1c2c2b4..167bd22 100644
--- a/routing_algo.c
+++ b/routing_algo.c
@@ -107,6 +107,7 @@ static int print_routing_algos(struct state *state)
 	nl_cb_err(cb, NL_CB_CUSTOM, netlink_print_error, NULL);
 
 	nl_recvmsgs(state->sock, cb);
+	nl_cb_put(cb);
 
 	if (!last_err) {
 		netlink_print_remaining_header(&opts);
diff --git a/throughputmeter.c b/throughputmeter.c
index 98a9490..1690bda 100644
--- a/throughputmeter.c
+++ b/throughputmeter.c
@@ -158,13 +158,18 @@ static int tp_meter_start(struct state *state, struct ether_addr *dst_mac,
 	int err = 0;
 
 	cb = nl_cb_alloc(NL_CB_DEFAULT);
+	if (!cb)
+		return -ENOMEM;
+
 	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, tp_meter_cookie_callback,
 		  cookie);
 	nl_cb_err(cb, NL_CB_CUSTOM, tpmeter_nl_print_error, cookie);
 
 	msg = nlmsg_alloc();
-	if (!msg)
+	if (!msg) {
+		nl_cb_put(cb);
 		return -ENOMEM;
+	}
 
 	genlmsg_put(msg, NL_AUTO_PID, NL_AUTO_SEQ, state->batadv_family, 0,
 		    0, BATADV_CMD_TP_METER, 1);
@@ -200,6 +205,9 @@ static int tp_recv_result(struct nl_sock *sock, struct tp_result *result)
 	int err = 0;
 
 	cb = nl_cb_alloc(NL_CB_DEFAULT);
+	if (!cb)
+		return -ENOMEM;
+
 	nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, no_seq_check, NULL);
 	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, tp_meter_result_callback,
 		  result);

-- 
2.47.3