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authorUlrich Drepper <drepper@redhat.com>2004-12-10 01:36:18 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-10 01:36:18 +0000
commitdc165f7b0bfa73ebd64584331d0cb7c2ead66147 (patch)
treef8f707e664d5dec91bc08f5796f967ae5d886b4c /malloc/malloc.c
parentbf7c04cd5f4b3a7d3e3155b0035396e7f1037a13 (diff)
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Update.
2004-12-09  Ulrich Drepper  <drepper@redhat.com>

	* malloc/malloc.c (public_rEALLOc): Add parameter checks.
	(_int_free): Provide better error message for invalid pointers.
Diffstat (limited to 'malloc/malloc.c')
-rw-r--r--malloc/malloc.c15
1 files changed, 13 insertions, 2 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c
index b62ffb57c0..cf1b935ffd 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -3434,6 +3434,17 @@ public_rEALLOc(Void_t* oldmem, size_t bytes)
   oldp    = mem2chunk(oldmem);
   oldsize = chunksize(oldp);
 
+  /* Little security check which won't hurt performance: the
+     allocator never wrapps around at the end of the address space.
+     Therefore we can exclude some size values which might appear
+     here by accident or by "design" from some intruder.  */
+  if (__builtin_expect ((uintptr_t) oldp > (uintptr_t) -oldsize, 0)
+      || __builtin_expect ((uintptr_t) oldp & MALLOC_ALIGN_MASK, 0))
+    {
+      malloc_printerr (check_action, "realloc(): invalid pointer", oldmem);
+      return NULL;
+    }
+
   checked_request2size(bytes, nb);
 
 #if HAVE_MMAP
@@ -4205,7 +4216,6 @@ _int_free(mstate av, Void_t* mem)
   mchunkptr       bck;         /* misc temp for linking */
   mchunkptr       fwd;         /* misc temp for linking */
 
-
   const char *errstr = NULL;
 
   p = mem2chunk(mem);
@@ -4215,7 +4225,8 @@ _int_free(mstate av, Void_t* mem)
      allocator never wrapps around at the end of the address space.
      Therefore we can exclude some size values which might appear
      here by accident or by "design" from some intruder.  */
-  if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0))
+  if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0)
+      || __builtin_expect ((uintptr_t) p & MALLOC_ALIGN_MASK, 0))
     {
       errstr = "free(): invalid pointer";
     errout: