1 /*
2  *  Buffer-based memory allocator
3  *
4  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5  *  SPDX-License-Identifier: GPL-2.0
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License along
18  *  with this program; if not, write to the Free Software Foundation, Inc.,
19  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  *  This file is part of mbed TLS (https://tls.mbed.org)
22  */
23 
24 #if !defined(MBEDTLS_CONFIG_FILE)
25 #include "mbedtls/config.h"
26 #else
27 #include MBEDTLS_CONFIG_FILE
28 #endif
29 
30 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
31 #include "mbedtls/memory_buffer_alloc.h"
32 
33 /* No need for the header guard as MBEDTLS_MEMORY_BUFFER_ALLOC_C
34    is dependent upon MBEDTLS_PLATFORM_C */
35 #include "mbedtls/platform.h"
36 
37 #include <string.h>
38 
39 #if defined(MBEDTLS_MEMORY_BACKTRACE)
40 #include <execinfo.h>
41 #endif
42 
43 #if defined(MBEDTLS_THREADING_C)
44 #include "mbedtls/threading.h"
45 #endif
46 
47 /* Implementation that should never be optimized out by the compiler */
48 static void mbedtls_zeroize( void *v, size_t n ) {
49     volatile unsigned char *p = v; while( n-- ) *p++ = 0;
50 }
51 
52 #define MAGIC1       0xFF00AA55
53 #define MAGIC2       0xEE119966
54 #define MAX_BT 20
55 
56 typedef struct _memory_header memory_header;
57 struct _memory_header
58 {
59     size_t          magic1;
60     size_t          size;
61     size_t          alloc;
62     memory_header   *prev;
63     memory_header   *next;
64     memory_header   *prev_free;
65     memory_header   *next_free;
66 #if defined(MBEDTLS_MEMORY_BACKTRACE)
67     char            **trace;
68     size_t          trace_count;
69 #endif
70     size_t          magic2;
71 };
72 
73 typedef struct
74 {
75     unsigned char   *buf;
76     size_t          len;
77     memory_header   *first;
78     memory_header   *first_free;
79     int             verify;
80 #if defined(MBEDTLS_MEMORY_DEBUG)
81     size_t          alloc_count;
82     size_t          free_count;
83     size_t          total_used;
84     size_t          maximum_used;
85     size_t          header_count;
86     size_t          maximum_header_count;
87 #endif
88 #if defined(MBEDTLS_THREADING_C)
89     mbedtls_threading_mutex_t   mutex;
90 #endif
91 }
92 buffer_alloc_ctx;
93 
94 static buffer_alloc_ctx heap;
95 
96 #if defined(MBEDTLS_MEMORY_DEBUG)
97 static void debug_header( memory_header *hdr )
98 {
99 #if defined(MBEDTLS_MEMORY_BACKTRACE)
100     size_t i;
101 #endif
102 
103     mbedtls_fprintf( stderr, "HDR:  PTR(%10zu), PREV(%10zu), NEXT(%10zu), "
104                               "ALLOC(%zu), SIZE(%10zu)\n",
105                       (size_t) hdr, (size_t) hdr->prev, (size_t) hdr->next,
106                       hdr->alloc, hdr->size );
107     mbedtls_fprintf( stderr, "      FPREV(%10zu), FNEXT(%10zu)\n",
108                       (size_t) hdr->prev_free, (size_t) hdr->next_free );
109 
110 #if defined(MBEDTLS_MEMORY_BACKTRACE)
111     mbedtls_fprintf( stderr, "TRACE: \n" );
112     for( i = 0; i < hdr->trace_count; i++ )
113         mbedtls_fprintf( stderr, "%s\n", hdr->trace[i] );
114     mbedtls_fprintf( stderr, "\n" );
115 #endif
116 }
117 
118 static void debug_chain()
119 {
120     memory_header *cur = heap.first;
121 
122     mbedtls_fprintf( stderr, "\nBlock list\n" );
123     while( cur != NULL )
124     {
125         debug_header( cur );
126         cur = cur->next;
127     }
128 
129     mbedtls_fprintf( stderr, "Free list\n" );
130     cur = heap.first_free;
131 
132     while( cur != NULL )
133     {
134         debug_header( cur );
135         cur = cur->next_free;
136     }
137 }
138 #endif /* MBEDTLS_MEMORY_DEBUG */
139 
140 static int verify_header( memory_header *hdr )
141 {
142     if( hdr->magic1 != MAGIC1 )
143     {
144 #if defined(MBEDTLS_MEMORY_DEBUG)
145         mbedtls_fprintf( stderr, "FATAL: MAGIC1 mismatch\n" );
146 #endif
147         return( 1 );
148     }
149 
150     if( hdr->magic2 != MAGIC2 )
151     {
152 #if defined(MBEDTLS_MEMORY_DEBUG)
153         mbedtls_fprintf( stderr, "FATAL: MAGIC2 mismatch\n" );
154 #endif
155         return( 1 );
156     }
157 
158     if( hdr->alloc > 1 )
159     {
160 #if defined(MBEDTLS_MEMORY_DEBUG)
161         mbedtls_fprintf( stderr, "FATAL: alloc has illegal value\n" );
162 #endif
163         return( 1 );
164     }
165 
166     if( hdr->prev != NULL && hdr->prev == hdr->next )
167     {
168 #if defined(MBEDTLS_MEMORY_DEBUG)
169         mbedtls_fprintf( stderr, "FATAL: prev == next\n" );
170 #endif
171         return( 1 );
172     }
173 
174     if( hdr->prev_free != NULL && hdr->prev_free == hdr->next_free )
175     {
176 #if defined(MBEDTLS_MEMORY_DEBUG)
177         mbedtls_fprintf( stderr, "FATAL: prev_free == next_free\n" );
178 #endif
179         return( 1 );
180     }
181 
182     return( 0 );
183 }
184 
185 static int verify_chain()
186 {
187     memory_header *prv = heap.first, *cur;
188 
189     if( prv == NULL || verify_header( prv ) != 0 )
190     {
191 #if defined(MBEDTLS_MEMORY_DEBUG)
192         mbedtls_fprintf( stderr, "FATAL: verification of first header "
193                                   "failed\n" );
194 #endif
195         return( 1 );
196     }
197 
198     if( heap.first->prev != NULL )
199     {
200 #if defined(MBEDTLS_MEMORY_DEBUG)
201         mbedtls_fprintf( stderr, "FATAL: verification failed: "
202                                   "first->prev != NULL\n" );
203 #endif
204         return( 1 );
205     }
206 
207     cur = heap.first->next;
208 
209     while( cur != NULL )
210     {
211         if( verify_header( cur ) != 0 )
212         {
213 #if defined(MBEDTLS_MEMORY_DEBUG)
214             mbedtls_fprintf( stderr, "FATAL: verification of header "
215                                       "failed\n" );
216 #endif
217             return( 1 );
218         }
219 
220         if( cur->prev != prv )
221         {
222 #if defined(MBEDTLS_MEMORY_DEBUG)
223             mbedtls_fprintf( stderr, "FATAL: verification failed: "
224                                       "cur->prev != prv\n" );
225 #endif
226             return( 1 );
227         }
228 
229         prv = cur;
230         cur = cur->next;
231     }
232 
233     return( 0 );
234 }
235 
236 static void *buffer_alloc_calloc( size_t n, size_t size )
237 {
238     memory_header *new, *cur = heap.first_free;
239     unsigned char *p;
240     void *ret;
241     size_t original_len, len;
242 #if defined(MBEDTLS_MEMORY_BACKTRACE)
243     void *trace_buffer[MAX_BT];
244     size_t trace_cnt;
245 #endif
246 
247     if( heap.buf == NULL || heap.first == NULL )
248         return( NULL );
249 
250     original_len = len = n * size;
251 
252     if( n == 0 || size == 0 || len / n != size )
253         return( NULL );
254     else if( len > (size_t)-MBEDTLS_MEMORY_ALIGN_MULTIPLE )
255         return( NULL );
256 
257     if( len % MBEDTLS_MEMORY_ALIGN_MULTIPLE )
258     {
259         len -= len % MBEDTLS_MEMORY_ALIGN_MULTIPLE;
260         len += MBEDTLS_MEMORY_ALIGN_MULTIPLE;
261     }
262 
263     // Find block that fits
264     //
265     while( cur != NULL )
266     {
267         if( cur->size >= len )
268             break;
269 
270         cur = cur->next_free;
271     }
272 
273     if( cur == NULL )
274         return( NULL );
275 
276     if( cur->alloc != 0 )
277     {
278 #if defined(MBEDTLS_MEMORY_DEBUG)
279         mbedtls_fprintf( stderr, "FATAL: block in free_list but allocated "
280                                   "data\n" );
281 #endif
282         mbedtls_exit( 1 );
283     }
284 
285 #if defined(MBEDTLS_MEMORY_DEBUG)
286     heap.alloc_count++;
287 #endif
288 
289     // Found location, split block if > memory_header + 4 room left
290     //
291     if( cur->size - len < sizeof(memory_header) +
292                           MBEDTLS_MEMORY_ALIGN_MULTIPLE )
293     {
294         cur->alloc = 1;
295 
296         // Remove from free_list
297         //
298         if( cur->prev_free != NULL )
299             cur->prev_free->next_free = cur->next_free;
300         else
301             heap.first_free = cur->next_free;
302 
303         if( cur->next_free != NULL )
304             cur->next_free->prev_free = cur->prev_free;
305 
306         cur->prev_free = NULL;
307         cur->next_free = NULL;
308 
309 #if defined(MBEDTLS_MEMORY_DEBUG)
310         heap.total_used += cur->size;
311         if( heap.total_used > heap.maximum_used )
312             heap.maximum_used = heap.total_used;
313 #endif
314 #if defined(MBEDTLS_MEMORY_BACKTRACE)
315         trace_cnt = backtrace( trace_buffer, MAX_BT );
316         cur->trace = backtrace_symbols( trace_buffer, trace_cnt );
317         cur->trace_count = trace_cnt;
318 #endif
319 
320         if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 )
321             mbedtls_exit( 1 );
322 
323         ret = (unsigned char *) cur + sizeof( memory_header );
324         memset( ret, 0, original_len );
325 
326         return( ret );
327     }
328 
329     p = ( (unsigned char *) cur ) + sizeof(memory_header) + len;
330     new = (memory_header *) p;
331 
332     new->size = cur->size - len - sizeof(memory_header);
333     new->alloc = 0;
334     new->prev = cur;
335     new->next = cur->next;
336 #if defined(MBEDTLS_MEMORY_BACKTRACE)
337     new->trace = NULL;
338     new->trace_count = 0;
339 #endif
340     new->magic1 = MAGIC1;
341     new->magic2 = MAGIC2;
342 
343     if( new->next != NULL )
344         new->next->prev = new;
345 
346     // Replace cur with new in free_list
347     //
348     new->prev_free = cur->prev_free;
349     new->next_free = cur->next_free;
350     if( new->prev_free != NULL )
351         new->prev_free->next_free = new;
352     else
353         heap.first_free = new;
354 
355     if( new->next_free != NULL )
356         new->next_free->prev_free = new;
357 
358     cur->alloc = 1;
359     cur->size = len;
360     cur->next = new;
361     cur->prev_free = NULL;
362     cur->next_free = NULL;
363 
364 #if defined(MBEDTLS_MEMORY_DEBUG)
365     heap.header_count++;
366     if( heap.header_count > heap.maximum_header_count )
367         heap.maximum_header_count = heap.header_count;
368     heap.total_used += cur->size;
369     if( heap.total_used > heap.maximum_used )
370         heap.maximum_used = heap.total_used;
371 #endif
372 #if defined(MBEDTLS_MEMORY_BACKTRACE)
373     trace_cnt = backtrace( trace_buffer, MAX_BT );
374     cur->trace = backtrace_symbols( trace_buffer, trace_cnt );
375     cur->trace_count = trace_cnt;
376 #endif
377 
378     if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 )
379         mbedtls_exit( 1 );
380 
381     ret = (unsigned char *) cur + sizeof( memory_header );
382     memset( ret, 0, original_len );
383 
384     return( ret );
385 }
386 
387 static void buffer_alloc_free( void *ptr )
388 {
389     memory_header *hdr, *old = NULL;
390     unsigned char *p = (unsigned char *) ptr;
391 
392     if( ptr == NULL || heap.buf == NULL || heap.first == NULL )
393         return;
394 
395     if( p < heap.buf || p >= heap.buf + heap.len )
396     {
397 #if defined(MBEDTLS_MEMORY_DEBUG)
398         mbedtls_fprintf( stderr, "FATAL: mbedtls_free() outside of managed "
399                                   "space\n" );
400 #endif
401         mbedtls_exit( 1 );
402     }
403 
404     p -= sizeof(memory_header);
405     hdr = (memory_header *) p;
406 
407     if( verify_header( hdr ) != 0 )
408         mbedtls_exit( 1 );
409 
410     if( hdr->alloc != 1 )
411     {
412 #if defined(MBEDTLS_MEMORY_DEBUG)
413         mbedtls_fprintf( stderr, "FATAL: mbedtls_free() on unallocated "
414                                   "data\n" );
415 #endif
416         mbedtls_exit( 1 );
417     }
418 
419     hdr->alloc = 0;
420 
421 #if defined(MBEDTLS_MEMORY_DEBUG)
422     heap.free_count++;
423     heap.total_used -= hdr->size;
424 #endif
425 
426 #if defined(MBEDTLS_MEMORY_BACKTRACE)
427     free( hdr->trace );
428     hdr->trace = NULL;
429     hdr->trace_count = 0;
430 #endif
431 
432     // Regroup with block before
433     //
434     if( hdr->prev != NULL && hdr->prev->alloc == 0 )
435     {
436 #if defined(MBEDTLS_MEMORY_DEBUG)
437         heap.header_count--;
438 #endif
439         hdr->prev->size += sizeof(memory_header) + hdr->size;
440         hdr->prev->next = hdr->next;
441         old = hdr;
442         hdr = hdr->prev;
443 
444         if( hdr->next != NULL )
445             hdr->next->prev = hdr;
446 
447         memset( old, 0, sizeof(memory_header) );
448     }
449 
450     // Regroup with block after
451     //
452     if( hdr->next != NULL && hdr->next->alloc == 0 )
453     {
454 #if defined(MBEDTLS_MEMORY_DEBUG)
455         heap.header_count--;
456 #endif
457         hdr->size += sizeof(memory_header) + hdr->next->size;
458         old = hdr->next;
459         hdr->next = hdr->next->next;
460 
461         if( hdr->prev_free != NULL || hdr->next_free != NULL )
462         {
463             if( hdr->prev_free != NULL )
464                 hdr->prev_free->next_free = hdr->next_free;
465             else
466                 heap.first_free = hdr->next_free;
467 
468             if( hdr->next_free != NULL )
469                 hdr->next_free->prev_free = hdr->prev_free;
470         }
471 
472         hdr->prev_free = old->prev_free;
473         hdr->next_free = old->next_free;
474 
475         if( hdr->prev_free != NULL )
476             hdr->prev_free->next_free = hdr;
477         else
478             heap.first_free = hdr;
479 
480         if( hdr->next_free != NULL )
481             hdr->next_free->prev_free = hdr;
482 
483         if( hdr->next != NULL )
484             hdr->next->prev = hdr;
485 
486         memset( old, 0, sizeof(memory_header) );
487     }
488 
489     // Prepend to free_list if we have not merged
490     // (Does not have to stay in same order as prev / next list)
491     //
492     if( old == NULL )
493     {
494         hdr->next_free = heap.first_free;
495         if( heap.first_free != NULL )
496             heap.first_free->prev_free = hdr;
497         heap.first_free = hdr;
498     }
499 
500     if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_FREE ) && verify_chain() != 0 )
501         mbedtls_exit( 1 );
502 }
503 
504 void mbedtls_memory_buffer_set_verify( int verify )
505 {
506     heap.verify = verify;
507 }
508 
509 int mbedtls_memory_buffer_alloc_verify()
510 {
511     return verify_chain();
512 }
513 
514 #if defined(MBEDTLS_MEMORY_DEBUG)
515 void mbedtls_memory_buffer_alloc_status()
516 {
517     mbedtls_fprintf( stderr,
518                       "Current use: %zu blocks / %zu bytes, max: %zu blocks / "
519                       "%zu bytes (total %zu bytes), alloc / free: %zu / %zu\n",
520                       heap.header_count, heap.total_used,
521                       heap.maximum_header_count, heap.maximum_used,
522                       heap.maximum_header_count * sizeof( memory_header )
523                       + heap.maximum_used,
524                       heap.alloc_count, heap.free_count );
525 
526     if( heap.first->next == NULL )
527     {
528         mbedtls_fprintf( stderr, "All memory de-allocated in stack buffer\n" );
529     }
530     else
531     {
532         mbedtls_fprintf( stderr, "Memory currently allocated:\n" );
533         debug_chain();
534     }
535 }
536 
537 void mbedtls_memory_buffer_alloc_max_get( size_t *max_used, size_t *max_blocks )
538 {
539     *max_used   = heap.maximum_used;
540     *max_blocks = heap.maximum_header_count;
541 }
542 
543 void mbedtls_memory_buffer_alloc_max_reset( void )
544 {
545     heap.maximum_used = 0;
546     heap.maximum_header_count = 0;
547 }
548 
549 void mbedtls_memory_buffer_alloc_cur_get( size_t *cur_used, size_t *cur_blocks )
550 {
551     *cur_used   = heap.total_used;
552     *cur_blocks = heap.header_count;
553 }
554 #endif /* MBEDTLS_MEMORY_DEBUG */
555 
556 #if defined(MBEDTLS_THREADING_C)
557 static void *buffer_alloc_calloc_mutexed( size_t n, size_t size )
558 {
559     void *buf;
560     if( mbedtls_mutex_lock( &heap.mutex ) != 0 )
561         return( NULL );
562     buf = buffer_alloc_calloc( n, size );
563     if( mbedtls_mutex_unlock( &heap.mutex ) )
564         return( NULL );
565     return( buf );
566 }
567 
568 static void buffer_alloc_free_mutexed( void *ptr )
569 {
570     /* We have to good option here, but corrupting the heap seems
571      * worse than loosing memory. */
572     if( mbedtls_mutex_lock( &heap.mutex ) )
573         return;
574     buffer_alloc_free( ptr );
575     (void) mbedtls_mutex_unlock( &heap.mutex );
576 }
577 #endif /* MBEDTLS_THREADING_C */
578 
579 void mbedtls_memory_buffer_alloc_init( unsigned char *buf, size_t len )
580 {
581     memset( &heap, 0, sizeof( buffer_alloc_ctx ) );
582 
583 #if defined(MBEDTLS_THREADING_C)
584     mbedtls_mutex_init( &heap.mutex );
585     mbedtls_platform_set_calloc_free( buffer_alloc_calloc_mutexed,
586                               buffer_alloc_free_mutexed );
587 #else
588     mbedtls_platform_set_calloc_free( buffer_alloc_calloc, buffer_alloc_free );
589 #endif
590 
591     if( len < sizeof( memory_header ) + MBEDTLS_MEMORY_ALIGN_MULTIPLE )
592         return;
593     else if( (size_t)buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE )
594     {
595         /* Adjust len first since buf is used in the computation */
596         len -= MBEDTLS_MEMORY_ALIGN_MULTIPLE
597              - (size_t)buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE;
598         buf += MBEDTLS_MEMORY_ALIGN_MULTIPLE
599              - (size_t)buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE;
600     }
601 
602     memset( buf, 0, len );
603 
604     heap.buf = buf;
605     heap.len = len;
606 
607     heap.first = (memory_header *)buf;
608     heap.first->size = len - sizeof( memory_header );
609     heap.first->magic1 = MAGIC1;
610     heap.first->magic2 = MAGIC2;
611     heap.first_free = heap.first;
612 }
613 
614 void mbedtls_memory_buffer_alloc_free()
615 {
616 #if defined(MBEDTLS_THREADING_C)
617     mbedtls_mutex_free( &heap.mutex );
618 #endif
619     mbedtls_zeroize( &heap, sizeof(buffer_alloc_ctx) );
620 }
621 
622 #if defined(MBEDTLS_SELF_TEST)
623 static int check_pointer( void *p )
624 {
625     if( p == NULL )
626         return( -1 );
627 
628     if( (size_t) p % MBEDTLS_MEMORY_ALIGN_MULTIPLE != 0 )
629         return( -1 );
630 
631     return( 0 );
632 }
633 
634 static int check_all_free( )
635 {
636     if(
637 #if defined(MBEDTLS_MEMORY_DEBUG)
638         heap.total_used != 0 ||
639 #endif
640         heap.first != heap.first_free ||
641         (void *) heap.first != (void *) heap.buf )
642     {
643         return( -1 );
644     }
645 
646     return( 0 );
647 }
648 
649 #define TEST_ASSERT( condition )            \
650     if( ! (condition) )                     \
651     {                                       \
652         if( verbose != 0 )                  \
653             mbedtls_printf( "failed\n" );  \
654                                             \
655         ret = 1;                            \
656         goto cleanup;                       \
657     }
658 
659 int mbedtls_memory_buffer_alloc_self_test( int verbose )
660 {
661     unsigned char buf[1024];
662     unsigned char *p, *q, *r, *end;
663     int ret = 0;
664 
665     if( verbose != 0 )
666         mbedtls_printf( "  MBA test #1 (basic alloc-free cycle): " );
667 
668     mbedtls_memory_buffer_alloc_init( buf, sizeof( buf ) );
669 
670     p = mbedtls_calloc( 1, 1 );
671     q = mbedtls_calloc( 1, 128 );
672     r = mbedtls_calloc( 1, 16 );
673 
674     TEST_ASSERT( check_pointer( p ) == 0 &&
675                  check_pointer( q ) == 0 &&
676                  check_pointer( r ) == 0 );
677 
678     mbedtls_free( r );
679     mbedtls_free( q );
680     mbedtls_free( p );
681 
682     TEST_ASSERT( check_all_free( ) == 0 );
683 
684     /* Memorize end to compare with the next test */
685     end = heap.buf + heap.len;
686 
687     mbedtls_memory_buffer_alloc_free( );
688 
689     if( verbose != 0 )
690         mbedtls_printf( "passed\n" );
691 
692     if( verbose != 0 )
693         mbedtls_printf( "  MBA test #2 (buf not aligned): " );
694 
695     mbedtls_memory_buffer_alloc_init( buf + 1, sizeof( buf ) - 1 );
696 
697     TEST_ASSERT( heap.buf + heap.len == end );
698 
699     p = mbedtls_calloc( 1, 1 );
700     q = mbedtls_calloc( 1, 128 );
701     r = mbedtls_calloc( 1, 16 );
702 
703     TEST_ASSERT( check_pointer( p ) == 0 &&
704                  check_pointer( q ) == 0 &&
705                  check_pointer( r ) == 0 );
706 
707     mbedtls_free( r );
708     mbedtls_free( q );
709     mbedtls_free( p );
710 
711     TEST_ASSERT( check_all_free( ) == 0 );
712 
713     mbedtls_memory_buffer_alloc_free( );
714 
715     if( verbose != 0 )
716         mbedtls_printf( "passed\n" );
717 
718     if( verbose != 0 )
719         mbedtls_printf( "  MBA test #3 (full): " );
720 
721     mbedtls_memory_buffer_alloc_init( buf, sizeof( buf ) );
722 
723     p = mbedtls_calloc( 1, sizeof( buf ) - sizeof( memory_header ) );
724 
725     TEST_ASSERT( check_pointer( p ) == 0 );
726     TEST_ASSERT( mbedtls_calloc( 1, 1 ) == NULL );
727 
728     mbedtls_free( p );
729 
730     p = mbedtls_calloc( 1, sizeof( buf ) - 2 * sizeof( memory_header ) - 16 );
731     q = mbedtls_calloc( 1, 16 );
732 
733     TEST_ASSERT( check_pointer( p ) == 0 && check_pointer( q ) == 0 );
734     TEST_ASSERT( mbedtls_calloc( 1, 1 ) == NULL );
735 
736     mbedtls_free( q );
737 
738     TEST_ASSERT( mbedtls_calloc( 1, 17 ) == NULL );
739 
740     mbedtls_free( p );
741 
742     TEST_ASSERT( check_all_free( ) == 0 );
743 
744     mbedtls_memory_buffer_alloc_free( );
745 
746     if( verbose != 0 )
747         mbedtls_printf( "passed\n" );
748 
749 cleanup:
750     mbedtls_memory_buffer_alloc_free( );
751 
752     return( ret );
753 }
754 #endif /* MBEDTLS_SELF_TEST */
755 
756 #endif /* MBEDTLS_MEMORY_BUFFER_ALLOC_C */
757