Fix: power of 2 size check should apply to size_t type, not uint32_t

[lttng-ust.git] / libringbuffer / ring_buffer_backend.c

diff --git a/libringbuffer/ring_buffer_backend.c b/libringbuffer/ring_buffer_backend.c
index dead69600f7a06391d9b276e348820eb0a59208a..e949a5e292d2048f306760f329f64d668a0c30cd 100644 (file)
--- a/libringbuffer/ring_buffer_backend.c
+++ b/libringbuffer/ring_buffer_backend.c
@@ -6,7 +6,9 @@
  * Dual LGPL v2.1/GPL v2 license.
  */
 
+#define _GNU_SOURCE
 #include <urcu/arch.h>
+#include <limits.h>
 
 #include <lttng/ringbuffer-config.h>
 #include "vatomic.h"
@@ -216,10 +218,13 @@ int channel_backend_init(struct channel_backend *chanb,
                return -EINVAL;
 
        /*
-        * Make sure the number of subbuffers and subbuffer size are power of 2.
+        * Make sure the number of subbuffers and subbuffer size are
+        * power of 2, and nonzero.
         */
-       CHAN_WARN_ON(chanb, hweight32(subbuf_size) != 1);
-       CHAN_WARN_ON(chanb, hweight32(num_subbuf) != 1);
+       if (!subbuf_size || (subbuf_size & (subbuf_size - 1)))
+               return -EINVAL;
+       if (!num_subbuf || (num_subbuf & (num_subbuf - 1)))
+               return -EINVAL;
 
        ret = subbuffer_id_check_index(config, num_subbuf);
        if (ret)