Fix: ensure kernel context is in a list before trying to delete it

[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 b4dc1b9e81e46765f523cda523a3c26a864dd106..fa207bc67eb1adc8e18a13ba27c583424f6d8a8d 100644 (file)
--- a/src/bin/lttng-sessiond/trace-kernel.c
+++ b/src/bin/lttng-sessiond/trace-kernel.c
@@ -15,7 +15,6 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#define _GNU_SOURCE
 #define _LGPL_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
@@ -241,11 +240,33 @@ struct ltt_kernel_context *trace_kernel_create_context(
        if (ctx) {
                memcpy(&kctx->ctx, ctx, sizeof(kctx->ctx));
        }
+error:
+       return kctx;
+}
+
+/*
+ * Allocate and init a kernel context object from an existing kernel context
+ * object.
+ *
+ * Return the allocated object or NULL on error.
+ */
+struct ltt_kernel_context *trace_kernel_copy_context(
+               struct ltt_kernel_context *kctx)
+{
+       struct ltt_kernel_context *kctx_copy;
 
-       CDS_INIT_LIST_HEAD(&kctx->list);
+       assert(kctx);
+       kctx_copy = zmalloc(sizeof(*kctx_copy));
+       if (!kctx_copy) {
+               PERROR("zmalloc ltt_kernel_context");
+               goto error;
+       }
+
+       memcpy(kctx_copy, kctx, sizeof(*kctx_copy));
+       memset(&kctx_copy->list, 0, sizeof(kctx_copy->list));
 
 error:
-       return kctx;
+       return kctx_copy;
 }
 
 /*
@@ -463,7 +484,9 @@ void trace_kernel_destroy_context(struct ltt_kernel_context *ctx)
 {
        assert(ctx);
 
-       cds_list_del(&ctx->list);
+       if (ctx->in_list) {
+               cds_list_del(&ctx->list);
+       }
        free(ctx);
 }