[v3,12/28] hw/i386/multiboot: Replace g_memdup() by g_memdup2()

Commit Message

Philippe Mathieu-Daudé Sept. 3, 2021, 5:44 p.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() wrapper.

Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 hw/i386/multiboot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/hw/i386/multiboot.c b/hw/i386/multiboot.c
index 9e7d69d4705..754415d17f3 100644
--- a/hw/i386/multiboot.c
+++ b/hw/i386/multiboot.c
@@ -387,7 +387,7 @@  int load_multiboot(FWCfgState *fw_cfg,
     mb_debug("           mb_mods_count = %d", mbs.mb_mods_count);
 
     /* save bootinfo off the stack */
-    mb_bootinfo_data = g_memdup(bootinfo, sizeof(bootinfo));
+    mb_bootinfo_data = g_memdup2(bootinfo, sizeof(bootinfo));
 
     /* Pass variables to option rom */
     fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ENTRY, mh_entry_addr);