libwimaxll: (fb Johannes Berg) fix handling of ack/nlerr in msg/reset/rfkill

We were not handling the thing properly and thus it was working only
by chance. We were missing the nlerr as reponses to messages.

The callbacks need to be setup to listen for the message we are
waiting for, ack and nlerr. And then we need to call nl_recvmsgs()
until the ack / or nlerr handler have been seen.

This makes the GENL_ADMIN_PERM setting in the kernel's policy flags work.

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>

1 files changed, 24 insertions, 8 deletions

diff --git a/lib/wimax.c b/lib/wimax.c
index 5af4126..650570b 100644
--- a/lib/wimax.c
+++ b/lib/wimax.c
@@ -78,8 +78,9 @@ int wimaxll_gnl_error_cb(struct sockaddr_nl *nla, struct nlmsgerr *nlerr,
 	d_fnstart(7, wmx, "(nla %p nlnerr %p [%d] mch %p)\n",
 		  nla, nlerr, nlerr->error, _mch);
 	wimaxll_mch_maybe_set_result(mch, nlerr->error);
-	d_fnend(7, wmx, "(nla %p nlnerr %p [%d] mch %p) = %d\n",
-		nla, nlerr, nlerr->error, _mch, NL_STOP);
+	mch->msg_done = 1;
+	d_fnend(7, wmx, "(nla %p nlnerr %p [%d] mch %p) = NL_STOP\n",
+		nla, nlerr, nlerr->error, _mch);
 	return NL_STOP;
 }
 
@@ -140,6 +141,7 @@ int wimaxll_gnl_ack_cb(struct nl_msg *msg, void *_mch)
 	if (nl_err->error < 0)
 		d_printf(2, NULL, "D: netlink ack: received netlink error %d\n",
 			  nl_err->error);
+	mch->msg_done = 1;
 error_ack_short:
 error_bad_type:
 	d_fnend(7, NULL, "(msg %p mch %p) = NL_STOP\n", msg, _mch);
@@ -168,17 +170,24 @@ int wimaxll_wait_for_ack(struct wimaxll_handle *wmx)
 
 	fake_mch.wmx = wmx;
 	fake_mch.result = -EINPROGRESS;
+	fake_mch.msg_done = 0;
 
 	cb = nl_socket_get_cb(wmx->nlh_tx);
 	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, wimaxll_gnl_ack_cb, &fake_mch);
 	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
 	nl_cb_err(cb, NL_CB_CUSTOM, wimaxll_gnl_error_cb, &fake_mch);
-	result = nl_recvmsgs_default(wmx->nlh_tx);
+	do
+		result = nl_recvmsgs(wmx->nlh_tx, cb);
+	while (fake_mch.msg_done == 0 && result >= 0);
+	result = fake_mch.result;
 	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
+	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
+	nl_cb_err(cb, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
 	nl_cb_put(cb);
 	if (result < 0)
 		return result;
-	return fake_mch.result;
+	else
+		return fake_mch.result;
 }
 
 
@@ -274,9 +283,6 @@ error_parse:
  *
  * This function simplifies waiting for that and getting the reply.
  *
- * You still need to wait for the ack in your function calling
- * nl_wait_for_ack().
- *
  * \note We use the same handler used for transmission in the TX side
  *     and it's callback set, that we modifiy. As noted in the doc for
  *     \a struct wimaxll_handle, each call site to nl_recvmsgs_default()
@@ -292,11 +298,21 @@ ssize_t wimaxll_wait_for_rp_result(struct wimaxll_handle *wmx)
 	d_fnstart(5, wmx, "(wmx %p)\n", wmx);
 	fake_mch.wmx = wmx;
 	fake_mch.result = -EINPROGRESS;
+	fake_mch.msg_done = 0;
 	cb = nl_socket_get_cb(wmx->nlh_tx);
+	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM,
+		  wimaxll_gnl_ack_cb, &fake_mch);
 	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM,
 		  wimaxll_gnl_rp_result_cb, &fake_mch);
 	nl_cb_err(cb, NL_CB_CUSTOM, wimaxll_gnl_error_cb, &fake_mch);
-	nl_recvmsgs_default(wmx->nlh_tx);
+	
+	do
+		result = nl_recvmsgs(wmx->nlh_tx, cb);
+	while (fake_mch.msg_done == 0 && result >= 0);
+	result = fake_mch.result;
+	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
+	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
+	nl_cb_err(cb, NL_CB_CUSTOM, NL_CB_DEFAULT, NULL);
 	nl_cb_put(cb);
 
 	result = fake_mch.result;