[PATCH BlueZ 1/2] core/advertising: Fix crash when unregistering advertisement too fast

[PATCH BlueZ 1/2] core/advertising: Fix crash when unregistering advertisement too fast

[Simon Mikuda]

When advertisement is unregistered during MGMT_OP_ADD_ADVERTISING it will
crash in add_adv_callback because struct btd_adv_client no longer exist.

This is seen also in debug log from bluetoothd:
bluetoothd[29698]: src/advertising.c:register_advertisement() RegisterAdvertisement
bluetoothd[29698]: src/advertising.c:client_create() Adding proxy for /org/bluez/example/advertisement0
bluetoothd[29698]: src/advertising.c:register_advertisement() Registered advertisement at path /org/bluez/example/advertisement0
bluetoothd[29698]: src/advertising.c:parse_service_uuids() Adding ServiceUUID: 180D
bluetoothd[29698]: src/advertising.c:parse_service_uuids() Adding ServiceUUID: 180F
bluetoothd[29698]: src/advertising.c:parse_manufacturer_data() Adding ManufacturerData for ffff
bluetoothd[29698]: src/advertising.c:parse_service_data() Adding ServiceData for 9999
bluetoothd[29698]: src/advertising.c:parse_data() Adding Data for type 0x26 len 3
bluetoothd[29698]: src/advertising.c:refresh_adv() Refreshing advertisement: /org/bluez/example/advertisement0
bluetoothd[29698]: src/advertising.c:unregister_advertisement() UnregisterAdvertisement
bluetoothd[29698]: src/advertising.c:add_adv_callback() Advertisement registered: �
Segmentation fault (core dumped)

Signed-off-by: Simon Mikuda <simon.mikuda@streamunlimited.com>
---
 src/advertising.c | 34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/src/advertising.c b/src/advertising.c
index 3ed1376..f53c14c 100644
--- a/src/advertising.c
+++ b/src/advertising.c
@@ -73,6 +73,7 @@ struct btd_adv_client {
 	uint16_t discoverable_to;
 	unsigned int to_id;
 	unsigned int disc_to_id;
+	unsigned int add_adv_id;
 	GDBusClient *client;
 	GDBusProxy *proxy;
 	DBusMessage *reg;
@@ -117,6 +118,15 @@ static void client_free(void *data)
 		g_dbus_client_unref(client->client);
 	}
 
+	if (client->reg) {
+		g_dbus_send_message(btd_get_dbus_connection(),
+				dbus_message_new_method_return(client->reg));
+		dbus_message_unref(client->reg);
+	}
+
+	if (client->add_adv_id)
+		mgmt_cancel(client->manager->mgmt, client->add_adv_id);
+
 	if (client->instance)
 		util_clear_uid(&client->manager->instance_bitmap,
 						client->instance);
@@ -765,7 +775,8 @@ static uint8_t *generate_scan_rsp(struct btd_adv_client *client,
 	return bt_ad_generate(client->scan, len);
 }
 
-static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
+static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func,
+						unsigned int *mgmt_id)
 {
 	struct mgmt_cp_add_advertising *cp;
 	uint8_t param_len;
@@ -774,6 +785,7 @@ static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
 	uint8_t *scan_rsp;
 	size_t scan_rsp_len = -1;
 	uint32_t flags = 0;
+	unsigned int mgmt_ret;
 
 	DBG("Refreshing advertisement: %s", client->path);
 
@@ -822,13 +834,17 @@ static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
 	free(adv_data);
 	free(scan_rsp);
 
-	if (!mgmt_send(client->manager->mgmt, MGMT_OP_ADD_ADVERTISING,
-				client->manager->mgmt_index, param_len, cp,
-				func, client, NULL)) {
+	mgmt_ret = mgmt_send(client->manager->mgmt, MGMT_OP_ADD_ADVERTISING,
+			client->manager->mgmt_index, param_len, cp,
+			func, client, NULL);
+
+	if (!mgmt_ret) {
 		error("Failed to add Advertising Data");
 		free(cp);
 		return -EINVAL;
 	}
+	if (mgmt_id)
+		*mgmt_id = mgmt_ret;
 
 	free(cp);
 
@@ -845,7 +861,7 @@ static gboolean client_discoverable_timeout(void *user_data)
 
 	bt_ad_clear_flags(client->data);
 
-	refresh_adv(client, NULL);
+	refresh_adv(client, NULL, NULL);
 
 	return FALSE;
 }
@@ -948,7 +964,7 @@ static void properties_changed(GDBusProxy *proxy, const char *name,
 			continue;
 
 		if (parser->func(iter, client)) {
-			refresh_adv(client, NULL);
+			refresh_adv(client, NULL, NULL);
 			break;
 		}
 	}
@@ -980,6 +996,8 @@ static void add_adv_callback(uint8_t status, uint16_t length,
 	struct btd_adv_client *client = user_data;
 	const struct mgmt_rp_add_advertising *rp = param;
 
+	client->add_adv_id = 0;
+
 	if (status)
 		goto done;
 
@@ -1059,7 +1077,7 @@ static DBusMessage *parse_advertisement(struct btd_adv_client *client)
 		goto fail;
 	}
 
-	err = refresh_adv(client, add_adv_callback);
+	err = refresh_adv(client, add_adv_callback, &client->add_adv_id);
 	if (!err)
 		return NULL;
 
@@ -1449,7 +1467,7 @@ void btd_adv_manager_destroy(struct btd_adv_manager *manager)
 
 static void manager_refresh(void *data, void *user_data)
 {
-	refresh_adv(data, user_data);
+	refresh_adv(data, user_data, NULL);
 }
 
 void btd_adv_manager_refresh(struct btd_adv_manager *manager)
-- 
2.7.4

[PATCH BlueZ 2/2] core/advertising: Fix crash when client is added after unregistration

[Simon Mikuda]

After "register_advertisement()" callback "client_proxy_added()" was yet
called but it was actually called after: "unregister_advertisement()" which
caused segmentation fault because client was removed twice.

Signed-off-by: Simon Mikuda <simon.mikuda@streamunlimited.com>
---
 src/advertising.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/advertising.c b/src/advertising.c
index f53c14c..45ff19f 100644
--- a/src/advertising.c
+++ b/src/advertising.c
@@ -190,6 +190,8 @@ static void client_remove(void *data)
 	struct btd_adv_client *client = data;
 	struct mgmt_cp_remove_advertising cp;
 
+	g_dbus_client_set_proxy_handlers(client->client, NULL, NULL, NULL,
+									client);
 	g_dbus_client_set_disconnect_watch(client->client, NULL, NULL);
 
 	cp.instance = client->instance;
-- 
2.7.4

Re: [PATCH BlueZ 1/2] core/advertising: Fix crash when unregistering advertisement too fast

[Luiz Augusto von Dentz]

Hi,

On Tue, Nov 12, 2019 at 3:59 PM Simon Mikuda
<simon.mikuda@streamunlimited.com> wrote:
>
> When advertisement is unregistered during MGMT_OP_ADD_ADVERTISING it will
> crash in add_adv_callback because struct btd_adv_client no longer exist.
>
> This is seen also in debug log from bluetoothd:
> bluetoothd[29698]: src/advertising.c:register_advertisement() RegisterAdvertisement
> bluetoothd[29698]: src/advertising.c:client_create() Adding proxy for /org/bluez/example/advertisement0
> bluetoothd[29698]: src/advertising.c:register_advertisement() Registered advertisement at path /org/bluez/example/advertisement0
> bluetoothd[29698]: src/advertising.c:parse_service_uuids() Adding ServiceUUID: 180D
> bluetoothd[29698]: src/advertising.c:parse_service_uuids() Adding ServiceUUID: 180F
> bluetoothd[29698]: src/advertising.c:parse_manufacturer_data() Adding ManufacturerData for ffff
> bluetoothd[29698]: src/advertising.c:parse_service_data() Adding ServiceData for 9999
> bluetoothd[29698]: src/advertising.c:parse_data() Adding Data for type 0x26 len 3
> bluetoothd[29698]: src/advertising.c:refresh_adv() Refreshing advertisement: /org/bluez/example/advertisement0
> bluetoothd[29698]: src/advertising.c:unregister_advertisement() UnregisterAdvertisement
> bluetoothd[29698]: src/advertising.c:add_adv_callback() Advertisement registered: �
> Segmentation fault (core dumped)
>
> Signed-off-by: Simon Mikuda <simon.mikuda@streamunlimited.com>
> ---
>  src/advertising.c | 34 ++++++++++++++++++++++++++--------
>  1 file changed, 26 insertions(+), 8 deletions(-)
>
> diff --git a/src/advertising.c b/src/advertising.c
> index 3ed1376..f53c14c 100644
> --- a/src/advertising.c
> +++ b/src/advertising.c
> @@ -73,6 +73,7 @@ struct btd_adv_client {
>         uint16_t discoverable_to;
>         unsigned int to_id;
>         unsigned int disc_to_id;
> +       unsigned int add_adv_id;
>         GDBusClient *client;
>         GDBusProxy *proxy;
>         DBusMessage *reg;
> @@ -117,6 +118,15 @@ static void client_free(void *data)
>                 g_dbus_client_unref(client->client);
>         }
>
> +       if (client->reg) {
> +               g_dbus_send_message(btd_get_dbus_connection(),
> +                               dbus_message_new_method_return(client->reg));
> +               dbus_message_unref(client->reg);
> +       }
> +
> +       if (client->add_adv_id)
> +               mgmt_cancel(client->manager->mgmt, client->add_adv_id);
> +
>         if (client->instance)
>                 util_clear_uid(&client->manager->instance_bitmap,
>                                                 client->instance);
> @@ -765,7 +775,8 @@ static uint8_t *generate_scan_rsp(struct btd_adv_client *client,
>         return bt_ad_generate(client->scan, len);
>  }
>
> -static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
> +static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func,
> +                                               unsigned int *mgmt_id)
>  {
>         struct mgmt_cp_add_advertising *cp;
>         uint8_t param_len;
> @@ -774,6 +785,7 @@ static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
>         uint8_t *scan_rsp;
>         size_t scan_rsp_len = -1;
>         uint32_t flags = 0;
> +       unsigned int mgmt_ret;
>
>         DBG("Refreshing advertisement: %s", client->path);
>
> @@ -822,13 +834,17 @@ static int refresh_adv(struct btd_adv_client *client, mgmt_request_func_t func)
>         free(adv_data);
>         free(scan_rsp);
>
> -       if (!mgmt_send(client->manager->mgmt, MGMT_OP_ADD_ADVERTISING,
> -                               client->manager->mgmt_index, param_len, cp,
> -                               func, client, NULL)) {
> +       mgmt_ret = mgmt_send(client->manager->mgmt, MGMT_OP_ADD_ADVERTISING,
> +                       client->manager->mgmt_index, param_len, cp,
> +                       func, client, NULL);
> +
> +       if (!mgmt_ret) {
>                 error("Failed to add Advertising Data");
>                 free(cp);
>                 return -EINVAL;
>         }
> +       if (mgmt_id)
> +               *mgmt_id = mgmt_ret;
>
>         free(cp);
>
> @@ -845,7 +861,7 @@ static gboolean client_discoverable_timeout(void *user_data)
>
>         bt_ad_clear_flags(client->data);
>
> -       refresh_adv(client, NULL);
> +       refresh_adv(client, NULL, NULL);
>
>         return FALSE;
>  }
> @@ -948,7 +964,7 @@ static void properties_changed(GDBusProxy *proxy, const char *name,
>                         continue;
>
>                 if (parser->func(iter, client)) {
> -                       refresh_adv(client, NULL);
> +                       refresh_adv(client, NULL, NULL);
>                         break;
>                 }
>         }
> @@ -980,6 +996,8 @@ static void add_adv_callback(uint8_t status, uint16_t length,
>         struct btd_adv_client *client = user_data;
>         const struct mgmt_rp_add_advertising *rp = param;
>
> +       client->add_adv_id = 0;
> +
>         if (status)
>                 goto done;
>
> @@ -1059,7 +1077,7 @@ static DBusMessage *parse_advertisement(struct btd_adv_client *client)
>                 goto fail;
>         }
>
> -       err = refresh_adv(client, add_adv_callback);
> +       err = refresh_adv(client, add_adv_callback, &client->add_adv_id);
>         if (!err)
>                 return NULL;
>
> @@ -1449,7 +1467,7 @@ void btd_adv_manager_destroy(struct btd_adv_manager *manager)
>
>  static void manager_refresh(void *data, void *user_data)
>  {
> -       refresh_adv(data, user_data);
> +       refresh_adv(data, user_data, NULL);
>  }
>
>  void btd_adv_manager_refresh(struct btd_adv_manager *manager)
> --
> 2.7.4

Applied, thanks.

-- 
Luiz Augusto von Dentz

[PATCH BlueZ 2/2] core/advertising: Fix crash when client is added after unregistration

[Simon Mikuda]

After "register_advertisement()" callback "client_proxy_added()" was yet
called but it was actually called after: "unregister_advertisement()" which
caused segmentation fault because client was removed twice.

Signed-off-by: Simon Mikuda <simon.mikuda@streamunlimited.com>
---
src/advertising.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/src/advertising.c b/src/advertising.c
index f53c14c..45ff19f 100644
--- a/src/advertising.c
+++ b/src/advertising.c
@@ -190,6 +190,8 @@ static void client_remove(void *data)
struct btd_adv_client *client = data;
struct mgmt_cp_remove_advertising cp;
+ g_dbus_client_set_proxy_handlers(client->client, NULL, NULL, NULL,
+ client);
g_dbus_client_set_disconnect_watch(client->client, NULL, NULL);
cp.instance = client->instance;

-- 
2.7.4

[PATCH BlueZ 2/2] core/advertising: Fix crash when client is added after unregistration

[Simon Mikuda]

After "register_advertisement()" callback "client_proxy_added()" was yet
called but it was actually called after: "unregister_advertisement()" which
caused segmentation fault because client was removed twice.

Signed-off-by: Simon Mikuda <simon.mikuda@streamunlimited.com>
---
 src/advertising.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/advertising.c b/src/advertising.c
index f53c14c..45ff19f 100644
--- a/src/advertising.c
+++ b/src/advertising.c
@@ -190,6 +190,8 @@ static void client_remove(void *data)
 	struct btd_adv_client *client = data;
 	struct mgmt_cp_remove_advertising cp;
 
+	g_dbus_client_set_proxy_handlers(client->client, NULL, NULL, NULL,
+									client);
 	g_dbus_client_set_disconnect_watch(client->client, NULL, NULL);
 
 	cp.instance = client->instance;
-- 
2.7.4