qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[PATCH 25/28] target/arm: Replace g_memdup() by g_memdup2_qemu()


From: Philippe Mathieu-Daudé
Subject: [PATCH 25/28] target/arm: Replace g_memdup() by g_memdup2_qemu()
Date: Fri, 3 Sep 2021 13:06:59 +0200

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 <philmd@redhat.com>
---
 target/arm/helper.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index a7ae78146d4..f3aeff399b9 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6242,8 +6242,9 @@ static void define_arm_vh_e2h_redirects_aliases(ARMCPU 
*cpu)
 
         /* Create alias before redirection so we dup the right data. */
         if (a->new_key) {
-            ARMCPRegInfo *new_reg = g_memdup(src_reg, sizeof(ARMCPRegInfo));
-            uint32_t *new_key = g_memdup(&a->new_key, sizeof(uint32_t));
+            ARMCPRegInfo *new_reg = g_memdup2_qemu(src_reg,
+                                                   sizeof(ARMCPRegInfo));
+            uint32_t *new_key = g_memdup2_qemu(&a->new_key, sizeof(uint32_t));
             bool ok;
 
             new_reg->name = a->new_name;
@@ -8818,7 +8819,7 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, const 
ARMCPRegInfo *r,
      * add a single reginfo struct to the hash table.
      */
     uint32_t *key = g_new(uint32_t, 1);
-    ARMCPRegInfo *r2 = g_memdup(r, sizeof(ARMCPRegInfo));
+    ARMCPRegInfo *r2 = g_memdup2_qemu(r, sizeof(ARMCPRegInfo));
     int is64 = (r->type & ARM_CP_64BIT) ? 1 : 0;
     int ns = (secstate & ARM_CP_SECSTATE_NS) ? 1 : 0;
 
-- 
2.31.1




reply via email to

[Prev in Thread] Current Thread [Next in Thread]