Fix: stream fd leaks on error

[lttng-ust.git] / liblttng-ust / lttng-ust-abi.c

diff --git a/liblttng-ust/lttng-ust-abi.c b/liblttng-ust/lttng-ust-abi.c
index 70ec22aa1ac8362ad244ed1c92caa3d032bcb244..1bf7a5aeab03a84b09c05dda0fdfe9ab8b7ead97 100644 (file)
--- a/liblttng-ust/lttng-ust-abi.c
+++ b/liblttng-ust/lttng-ust-abi.c
@@ -37,6 +37,7 @@
  *     - Takes instrumentation source specific arguments.
  */
 
+#define _LGPL_SOURCE
 #include <lttng/ust-abi.h>
 #include <lttng/ust-error.h>
 #include <urcu/compiler.h>
@@ -44,10 +45,12 @@
 #include <lttng/ust-events.h>
 #include <lttng/ust-version.h>
 #include <lttng/tracepoint.h>
+#include <ust-fd.h>
 #include "tracepoint-internal.h"
 #include <usterr-signal-safe.h>
 #include <helper.h>
 #include "lttng-tracer.h"
+#include "string-utils.h"
 #include "../libringbuffer/shm.h"
 #include "../libringbuffer/frontend_types.h"
 
@@ -185,6 +188,7 @@ static
 void objd_ref(int id)
 {
        struct lttng_ust_obj *obj = _objd_get(id);
+       assert(obj != NULL);
        obj->u.s.f_count++;
 }
 
@@ -207,7 +211,7 @@ int lttng_ust_objd_unref(int id, int is_owner)
        }
        if ((--obj->u.s.f_count) == 1) {
                const struct lttng_ust_objd_ops *ops = objd_ops(id);
-               
+
                if (ops->release)
                        ops->release(id);
                objd_free(id);
@@ -334,9 +338,10 @@ long lttng_abi_tracer_version(int objd,
 static
 long lttng_abi_add_context(int objd,
        struct lttng_ust_context *context_param,
+       union ust_args *uargs,
        struct lttng_ctx **ctx, struct lttng_session *session)
 {
-       return lttng_attach_context(context_param, ctx, session);
+       return lttng_attach_context(context_param, uargs, ctx, session);
 }
 
 /**
@@ -388,6 +393,7 @@ static const struct lttng_ust_objd_ops lttng_ops = {
        .cmd = lttng_cmd,
 };
 
+static
 int lttng_abi_map_channel(int session_objd,
                struct lttng_ust_channel *ust_chan,
                union ust_args *uargs,
@@ -403,11 +409,13 @@ int lttng_abi_map_channel(int session_objd,
        struct channel *chan;
        struct lttng_ust_lib_ring_buffer_config *config;
        void *chan_data;
+       int wakeup_fd;
        uint64_t len;
        int ret;
        enum lttng_ust_chan_type type;
 
        chan_data = uargs->channel.chan_data;
+       wakeup_fd = uargs->channel.wakeup_fd;
        len = ust_chan->len;
        type = ust_chan->type;
 
@@ -415,7 +423,8 @@ int lttng_abi_map_channel(int session_objd,
        case LTTNG_UST_CHAN_PER_CPU:
                break;
        default:
-               return -EINVAL;
+               ret = -EINVAL;
+               goto invalid;
        }
 
        if (session->been_active) {
@@ -423,12 +432,16 @@ int lttng_abi_map_channel(int session_objd,
                goto active;    /* Refuse to add channel to active session */
        }
 
-       channel_handle = channel_handle_create(chan_data, len);
+       channel_handle = channel_handle_create(chan_data, len, wakeup_fd);
        if (!channel_handle) {
                ret = -EINVAL;
                goto handle_error;
        }
 
+       /* Ownership of chan_data and wakeup_fd taken by channel handle. */
+       uargs->channel.chan_data = NULL;
+       uargs->channel.wakeup_fd = -1;
+
        chan = shmp(channel_handle, channel_handle->chan);
        assert(chan);
        chan->handle = channel_handle;
@@ -443,8 +456,19 @@ int lttng_abi_map_channel(int session_objd,
        switch (type) {
        case LTTNG_UST_CHAN_PER_CPU:
                if (config->output == RING_BUFFER_MMAP) {
-                       transport_name = config->mode == RING_BUFFER_OVERWRITE ?
-                               "relay-overwrite-mmap" : "relay-discard-mmap";
+                       if (config->mode == RING_BUFFER_OVERWRITE) {
+                               if (config->wakeup == RING_BUFFER_WAKEUP_BY_WRITER) {
+                                       transport_name = "relay-overwrite-mmap";
+                               } else {
+                                       transport_name = "relay-overwrite-rt-mmap";
+                               }
+                       } else {
+                               if (config->wakeup == RING_BUFFER_WAKEUP_BY_WRITER) {
+                                       transport_name = "relay-discard-mmap";
+                               } else {
+                                       transport_name = "relay-discard-rt-mmap";
+                               }
+                       }
                } else {
                        ret = -EINVAL;
                        goto notransport;
@@ -452,8 +476,6 @@ int lttng_abi_map_channel(int session_objd,
                chan_name = "channel";
                break;
        default:
-               transport_name = "<unknown>";
-               chan_name = "<unknown>";
                ret = -EINVAL;
                goto notransport;
        }
@@ -496,13 +518,16 @@ int lttng_abi_map_channel(int session_objd,
        objd_ref(session_objd);
        return chan_objd;
 
+       /* error path after channel was created */
 objd_error:
 notransport:
-       free(lttng_chan);
 alloc_error:
        channel_destroy(chan, channel_handle, 0);
+       return ret;
+
 handle_error:
 active:
+invalid:
        return ret;
 }
 
@@ -542,6 +567,8 @@ long lttng_session_cmd(int objd, unsigned int cmd, unsigned long arg,
        case LTTNG_UST_SESSION_STOP:
        case LTTNG_UST_DISABLE:
                return lttng_session_disable(session);
+       case LTTNG_UST_SESSION_STATEDUMP:
+               return lttng_session_statedump(session);
        default:
                return -EINVAL;
        }
@@ -745,6 +772,9 @@ int lttng_abi_map_stream(int channel_objd, struct lttng_ust_stream *info,
                info->stream_nr, info->len);
        if (ret)
                goto error_add_stream;
+       /* Take ownership of shm_fd and wakeup_fd. */
+       uargs->stream.shm_fd = -1;
+       uargs->stream.wakeup_fd = -1;
 
        return 0;
 
@@ -844,10 +874,14 @@ long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg,
        {
                struct lttng_ust_event *event_param =
                        (struct lttng_ust_event *) arg;
-               if (event_param->name[strlen(event_param->name) - 1] == '*') {
-                       /* If ends with wildcard, create wildcard. */
+
+               if (strutils_is_star_glob_pattern(event_param->name)) {
+                       /*
+                        * If the event name is a star globbing pattern,
+                        * we create the special star globbing enabler.
+                        */
                        return lttng_abi_create_enabler(objd, event_param,
-                                       owner, LTTNG_ENABLER_WILDCARD);
+                                       owner, LTTNG_ENABLER_STAR_GLOB);
                } else {
                        return lttng_abi_create_enabler(objd, event_param,
                                        owner, LTTNG_ENABLER_EVENT);
@@ -855,7 +889,7 @@ long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg,
        }
        case LTTNG_UST_CONTEXT:
                return lttng_abi_add_context(objd,
-                               (struct lttng_ust_context *) arg,
+                               (struct lttng_ust_context *) arg, uargs,
                                &channel->ctx, channel->session);
        case LTTNG_UST_ENABLE:
                return lttng_channel_enable(channel);
@@ -902,6 +936,8 @@ static const struct lttng_ust_objd_ops lttng_channel_ops = {
  *             Disable recording for this enabler
  *     LTTNG_UST_FILTER
  *             Attach a filter to an enabler.
+ *     LTTNG_UST_EXCLUSION
+ *             Attach exclusions to an enabler.
  */
 static
 long lttng_enabler_cmd(int objd, unsigned int cmd, unsigned long arg,
@@ -927,6 +963,11 @@ long lttng_enabler_cmd(int objd, unsigned int cmd, unsigned long arg,
                        return ret;
                return 0;
        }
+       case LTTNG_UST_EXCLUSION:
+       {
+               return lttng_enabler_attach_exclusion(enabler,
+                               (struct lttng_ust_excluder_node *) arg);
+       }
        default:
                return -EINVAL;
        }
@@ -950,6 +991,8 @@ static const struct lttng_ust_objd_ops lttng_enabler_ops = {
 void lttng_ust_abi_exit(void)
 {
        lttng_ust_abi_close_in_progress = 1;
+       ust_lock_nocheck();
        objd_table_destroy();
+       ust_unlock();
        lttng_ust_abi_close_in_progress = 0;
 }