/* SPDX-License-Identifier: LGPL-2.1+ */
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
+#include <malloc.h>
#include <stdint.h>
#include <string.h>
#include "alloc-util.h"
#include "macro.h"
-#include "util.h"
+#include "memory-util.h"
void* memdup(const void *p, size_t l) {
void *ret;
assert(l == 0 || p);
- ret = malloc(l);
+ ret = malloc(l ?: 1);
if (!ret)
return NULL;
/* The same as memdup() but place a safety NUL byte after the allocated memory */
+ if (_unlikely_(l == SIZE_MAX)) /* prevent overflow */
+ return NULL;
+
ret = malloc(l + 1);
if (!ret)
return NULL;
if (*allocated >= need)
return *p;
- newalloc = MAX(need * 2, 64u / size);
- a = newalloc * size;
+ if (_unlikely_(need > SIZE_MAX/2)) /* Overflow check */
+ return NULL;
- /* check for overflows */
- if (a < size * need)
+ newalloc = need * 2;
+ if (size_multiply_overflow(newalloc, size))
return NULL;
+ a = newalloc * size;
+ if (a < 64) /* Allocate at least 64 bytes */
+ a = 64;
+
q = realloc(*p, a);
if (!q)
return NULL;
+ if (size > 0) {
+ size_t bn;
+
+ /* Adjust for the 64 byte minimum */
+ newalloc = a / size;
+
+ bn = malloc_usable_size(q) / size;
+ if (bn > newalloc) {
+ void *qq;
+
+ /* The actual size allocated is larger than what we asked for. Let's call realloc() again to
+ * take possession of the extra space. This should be cheap, since libc doesn't have to move
+ * the memory for this. */
+
+ qq = reallocarray(q, bn, size);
+ if (_likely_(qq)) {
+ *p = qq;
+ *allocated = bn;
+ return qq;
+ }
+ }
+ }
+
*p = q;
*allocated = newalloc;
return q;