Fix: Align buffers from objstack_alloc on sizeof(void *)

The buffers from objstack_alloc will store pointers, so they must
be aligned on a pointer's size, or else it will cause issues on the
CPUs which do not support unaligned addresses access.

Signed-off-by: Fredrik Markstrom <fredrik.markstrom@gmail.com>
Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/formats/ctf/metadata/objstack.c b/formats/ctf/metadata/objstack.c
index 9e264a415d3311755489940c2a490c9255b34a17..14d925215b4316d7511bf822135d62318aa8efbe 100644 (file)
--- a/formats/ctf/metadata/objstack.c
+++ b/formats/ctf/metadata/objstack.c
@@ -27,6 +27,7 @@
 #include <stdlib.h>
 #include <babeltrace/list.h>
 #include <babeltrace/babeltrace-internal.h>
+#include <babeltrace/align.h>
 
 #define OBJSTACK_INIT_LEN              128
 #define OBJSTACK_POISON                        0xcc
@@ -39,7 +40,7 @@ struct objstack_node {
        struct bt_list_head node;
        size_t len;
        size_t used_len;
-       char data[];
+       char __attribute__ ((aligned (sizeof(void *)))) data[];
 };
 
 BT_HIDDEN
@@ -118,6 +119,8 @@ void *objstack_alloc(struct objstack *objstack, size_t len)
        struct objstack_node *last_node;
        void *p;
 
+       len = ALIGN(len, sizeof(void *));
+
        /* Get last node */
        last_node = bt_list_entry(objstack->head.prev,
                        struct objstack_node, node);