Fix: incorrect close of fd 0 for syscall kernel event destroy

[lttng-tools.git] / src / bin / lttng-sessiond / trace-kernel.c

diff --git a/src/bin/lttng-sessiond/trace-kernel.c b/src/bin/lttng-sessiond/trace-kernel.c
index 79e4a2f4e28b7e64a1f83fa242cf4677a570a7c4..68753286fb81c336e5026eb0eb64411ebbd5a81f 100644 (file)
--- a/src/bin/lttng-sessiond/trace-kernel.c
+++ b/src/bin/lttng-sessiond/trace-kernel.c
@@ -22,7 +22,6 @@
 #include <string.h>
 #include <unistd.h>
 
-#include <common/lttngerr.h>
 #include <common/common.h>
 #include <common/defaults.h>
 
@@ -185,8 +184,8 @@ struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev)
                attr->u.kprobe.addr = ev->attr.probe.addr;
                attr->u.kprobe.offset = ev->attr.probe.offset;
                strncpy(attr->u.kprobe.symbol_name,
-                               ev->attr.probe.symbol_name, LTTNG_SYM_NAME_LEN);
-               attr->u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+                               ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
+               attr->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
                break;
        case LTTNG_EVENT_FUNCTION:
                attr->instrumentation = LTTNG_KERNEL_KRETPROBE;
@@ -194,14 +193,14 @@ struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev)
                attr->u.kretprobe.offset = ev->attr.probe.offset;
                attr->u.kretprobe.offset = ev->attr.probe.offset;
                strncpy(attr->u.kretprobe.symbol_name,
-                               ev->attr.probe.symbol_name, LTTNG_SYM_NAME_LEN);
-               attr->u.kretprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+                               ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
+               attr->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
                break;
        case LTTNG_EVENT_FUNCTION_ENTRY:
                attr->instrumentation = LTTNG_KERNEL_FUNCTION;
                strncpy(attr->u.ftrace.symbol_name,
-                               ev->attr.ftrace.symbol_name, LTTNG_SYM_NAME_LEN);
-               attr->u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+                               ev->attr.ftrace.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
+               attr->u.ftrace.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
                break;
        case LTTNG_EVENT_TRACEPOINT:
                attr->instrumentation = LTTNG_KERNEL_TRACEPOINT;
@@ -218,8 +217,8 @@ struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev)
        }
 
        /* Copy event name */
-       strncpy(attr->name, ev->name, LTTNG_SYM_NAME_LEN);
-       attr->name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+       strncpy(attr->name, ev->name, LTTNG_KERNEL_SYM_NAME_LEN);
+       attr->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
 
        /* Setting up a kernel event */
        lke->fd = 0;
@@ -322,9 +321,13 @@ void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream)
  */
 void trace_kernel_destroy_event(struct ltt_kernel_event *event)
 {
-       DBG("[trace] Closing event fd %d", event->fd);
-       /* Close kernel fd */
-       close(event->fd);
+       if (event->fd >= 0) {
+               DBG("[trace] Closing event fd %d", event->fd);
+               /* Close kernel fd */
+               close(event->fd);
+       } else {
+               DBG("[trace] Tearing down event (no associated fd)");
+       }
 
        /* Remove from event list */
        cds_list_del(&event->list);