[05/28] block/qcow2-bitmap: Replace g_memdup() by g_memdup2_qemu()

Commit Message

Philippe Mathieu-Daudé Sept. 3, 2021, 11:06 a.m. UTC

Per https://discourse.gnome.org/t/port-your-module-from-g-memdup-to-g-memdup2-now/5538

  The old API took the size of the memory to duplicate as a guint,
  whereas most memory functions take memory sizes as a gsize. This
  made it easy to accidentally pass a gsize to g_memdup(). For large
  values, that would lead to a silent truncation of the size from 64
  to 32 bits, and result in a heap area being returned which is
  significantly smaller than what the caller expects. This can likely
  be exploited in various modules to cause a heap buffer overflow.

Replace g_memdup() by the safer g_memdup2_qemu() wrapper.

Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 block/qcow2-bitmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index 8fb47315515..ec303acb46b 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -1599,7 +1599,7 @@  bool qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
                            name);
                 goto fail;
             }
-            tb = g_memdup(&bm->table, sizeof(bm->table));
+            tb = g_memdup2_qemu(&bm->table, sizeof(bm->table));
             bm->table.offset = 0;
             bm->table.size = 0;
             QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry);