nettle/SOURCES/gmp-6.2.1-zeroize-allocator...

54 lines
1.4 KiB
Diff

diff -r e3123b88d012 memory.c
--- a/memory.c Tue Aug 16 22:02:45 2022 +0200
+++ b/memory.c Fri Aug 19 06:25:37 2022 +0900
@@ -29,7 +29,8 @@
see https://www.gnu.org/licenses/. */
#include <stdio.h>
-#include <stdlib.h> /* for malloc, realloc, free */
+#include <stdlib.h> /* for malloc, free */
+#include <string.h> /* for memcpy, explicit_bzero */
#include "gmp-impl.h"
@@ -98,11 +99,28 @@
new_size += 2 * GMP_LIMB_BYTES;
#endif
- ret = realloc (oldptr, new_size);
- if (ret == 0)
+ if (new_size == 0)
+ {
+ explicit_bzero (oldptr, old_size);
+ free (oldptr);
+ return NULL;
+ }
+ else if (old_size == new_size)
+ return oldptr;
+ else
{
- fprintf (stderr, "GNU MP: Cannot reallocate memory (old_size=%lu new_size=%lu)\n", (long) old_size, (long) new_size);
- abort ();
+ /* We can't simply call realloc, as it may allocate memory from
+ a different arena. */
+ ret = malloc (new_size);
+ if (ret == NULL)
+ {
+ fprintf (stderr, "GNU MP: Cannot reallocate memory (old_size=%lu new_size=%lu)\n", (long) old_size, (long) new_size);
+ explicit_bzero(oldptr, old_size);
+ abort();
+ }
+ memcpy (ret, oldptr, MIN(old_size, new_size));
+ explicit_bzero (oldptr, old_size);
+ free (oldptr);
}
#ifdef DEBUG
@@ -141,5 +159,6 @@
blk_ptr = p - 1;
}
#endif
+ explicit_bzero (blk_ptr, blk_size);
free (blk_ptr);
}