Fix metadata event arg (null pointer exception)

[lttng-modules.git] / ltt-debugfs-abi.c

diff --git a/ltt-debugfs-abi.c b/ltt-debugfs-abi.c
index d013fa5a86a4e1fd33507ceff92dab0c509386de..02f7232ccb67f2b89ac9d446f14bb2daf043d123 100644 (file)
--- a/ltt-debugfs-abi.c
+++ b/ltt-debugfs-abi.c
@@ -142,22 +142,19 @@ static
 void lttng_metadata_create_events(struct file *channel_file)
 {
        struct ltt_channel *channel = channel_file->private_data;
+       static struct lttng_kernel_event metadata_params = {
+               .instrumentation = LTTNG_KERNEL_TRACEPOINTS,
+               .name = "lttng_metadata",
+       };
        char *event_name = "lttng_metadata";
-       const struct lttng_event_desc *event_desc;
        struct ltt_event *event;
        int ret;
 
-       event_desc = ltt_event_get(event_name);
-       if (!event_desc) {
-               ret = -ENOENT;
-               goto get_error;
-       }
        /*
         * We tolerate no failure path after event creation. It will stay
         * invariant for the rest of the session.
         */
-       event = ltt_event_create(channel, event_name, LTTNG_KERNEL_TRACEPOINTS,
-                                event_desc, NULL);
+       event = ltt_event_create(channel, event_name, &metadata_params, NULL);
        if (!event) {
                goto create_error;
                ret = -EEXIST;
@@ -165,8 +162,6 @@ void lttng_metadata_create_events(struct file *channel_file)
        return;
 
 create_error:
-       ltt_event_put(event_desc);
-get_error:
        WARN_ON(1);
        return;         /* not allowed to return error */
 }
@@ -230,8 +225,8 @@ int lttng_abi_create_channel(struct file *session_file,
        chan_file->private_data = chan;
        fd_install(chan_fd, chan_file);
        if (channel_type == METADATA_CHANNEL) {
-               lttng_metadata_create_events(chan_file);
                session->metadata = chan;
+               lttng_metadata_create_events(chan_file);
        }
 
        /* The channel created holds a reference on the session */
@@ -359,7 +354,6 @@ int lttng_abi_create_event(struct file *channel_file,
                           struct lttng_kernel_event __user *uevent_param)
 {
        struct ltt_channel *channel = channel_file->private_data;
-       const struct lttng_event_desc *event_desc;
        struct ltt_event *event;
        char *event_name;
        struct lttng_kernel_event event_param;
@@ -376,11 +370,15 @@ int lttng_abi_create_event(struct file *channel_file,
                goto name_error;
        }
        event_name[PATH_MAX - 1] = '\0';
-
-       event_desc = ltt_event_get(event_name);
-       if (!event_desc) {
-               ret = -ENOENT;
-               goto get_error;
+       switch (event_param.instrumentation) {
+       case LTTNG_KERNEL_KPROBES:
+               event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+               break;
+       case LTTNG_KERNEL_FUNCTION_TRACER:
+               event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+               break;
+       default:
+               break;
        }
        event_fd = get_unused_fd();
        if (event_fd < 0) {
@@ -398,8 +396,7 @@ int lttng_abi_create_event(struct file *channel_file,
         * We tolerate no failure path after event creation. It will stay
         * invariant for the rest of the session.
         */
-       event = ltt_event_create(channel, event_name, &event_param,
-                                event_desc, NULL);
+       event = ltt_event_create(channel, event_name, &event_param, NULL);
        if (!event) {
                ret = -EEXIST;
                goto event_error;
@@ -416,8 +413,6 @@ event_error:
 file_error:
        put_unused_fd(event_fd);
 fd_error:
-       ltt_event_put(event_desc);
-get_error:
 name_error:
        kfree(event_name);
        return ret;