block/qcow2-bitmap: Replace g_memdup() by g_memdup2()
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() wrapper.
Trivially safe because the argument was directly from sizeof.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903174510.751630-6-philmd@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index 874ea56..256ec99 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -1609,7 +1609,7 @@
name);
goto fail;
}
- tb = g_memdup(&bm->table, sizeof(bm->table));
+ tb = g_memdup2(&bm->table, sizeof(bm->table));
bm->table.offset = 0;
bm->table.size = 0;
QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry);