calloc: Make sure we always have an overflow-checking calloc() available

This tries to make sure that everywhere in this source tree, we always have
an appropriate version of calloc() (i.e. grub_calloc(), xcalloc(), etc.)
available, and that they all safely check for overflow and return NULL when
it would occur.

Signed-off-by: Peter Jones <pjones@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Peter Jones 2020-06-15 12:15:29 -04:00 committed by Daniel Kiper
parent 68708c4503
commit 64e26162eb
7 changed files with 85 additions and 3 deletions

View file

@ -85,6 +85,18 @@ grub_util_error (const char *fmt, ...)
exit (1); exit (1);
} }
void *
xcalloc (grub_size_t nmemb, grub_size_t size)
{
void *p;
p = calloc (nmemb, size);
if (!p)
grub_util_error ("%s", _("out of memory"));
return p;
}
void * void *
xmalloc (grub_size_t size) xmalloc (grub_size_t size)
{ {

View file

@ -25,6 +25,16 @@
#include <string.h> #include <string.h>
#include <grub/i18n.h> #include <grub/i18n.h>
void *
grub_calloc (grub_size_t nmemb, grub_size_t size)
{
void *ret;
ret = calloc (nmemb, size);
if (!ret)
grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
return ret;
}
void * void *
grub_malloc (grub_size_t size) grub_malloc (grub_size_t size)
{ {

View file

@ -67,8 +67,10 @@
#include <grub/dl.h> #include <grub/dl.h>
#include <grub/i18n.h> #include <grub/i18n.h>
#include <grub/mm_private.h> #include <grub/mm_private.h>
#include <grub/safemath.h>
#ifdef MM_DEBUG #ifdef MM_DEBUG
# undef grub_calloc
# undef grub_malloc # undef grub_malloc
# undef grub_zalloc # undef grub_zalloc
# undef grub_realloc # undef grub_realloc
@ -375,6 +377,30 @@ grub_memalign (grub_size_t align, grub_size_t size)
return 0; return 0;
} }
/*
* Allocate NMEMB instances of SIZE bytes and return the pointer, or error on
* integer overflow.
*/
void *
grub_calloc (grub_size_t nmemb, grub_size_t size)
{
void *ret;
grub_size_t sz = 0;
if (grub_mul (nmemb, size, &sz))
{
grub_error (GRUB_ERR_OUT_OF_RANGE, N_("overflow is detected"));
return NULL;
}
ret = grub_memalign (0, sz);
if (!ret)
return NULL;
grub_memset (ret, 0, sz);
return ret;
}
/* Allocate SIZE bytes and return the pointer. */ /* Allocate SIZE bytes and return the pointer. */
void * void *
grub_malloc (grub_size_t size) grub_malloc (grub_size_t size)
@ -561,6 +587,20 @@ grub_mm_dump (unsigned lineno)
grub_printf ("\n"); grub_printf ("\n");
} }
void *
grub_debug_calloc (const char *file, int line, grub_size_t nmemb, grub_size_t size)
{
void *ptr;
if (grub_mm_debug)
grub_printf ("%s:%d: calloc (0x%" PRIxGRUB_SIZE ", 0x%" PRIxGRUB_SIZE ") = ",
file, line, size);
ptr = grub_calloc (nmemb, size);
if (grub_mm_debug)
grub_printf ("%p\n", ptr);
return ptr;
}
void * void *
grub_debug_malloc (const char *file, int line, grub_size_t size) grub_debug_malloc (const char *file, int line, grub_size_t size)
{ {

View file

@ -4,6 +4,7 @@
#include <grub/crypto.h> #include <grub/crypto.h>
#include <grub/dl.h> #include <grub/dl.h>
#include <grub/env.h> #include <grub/env.h>
#include <grub/safemath.h>
GRUB_MOD_LICENSE ("GPLv3+"); GRUB_MOD_LICENSE ("GPLv3+");
@ -36,7 +37,10 @@ void *
gcry_xcalloc (size_t n, size_t m) gcry_xcalloc (size_t n, size_t m)
{ {
void *ret; void *ret;
ret = grub_zalloc (n * m); size_t sz;
if (grub_mul (n, m, &sz))
grub_fatal ("gcry_xcalloc would overflow");
ret = grub_zalloc (sz);
if (!ret) if (!ret)
grub_fatal ("gcry_xcalloc failed"); grub_fatal ("gcry_xcalloc failed");
return ret; return ret;
@ -56,7 +60,10 @@ void *
gcry_xcalloc_secure (size_t n, size_t m) gcry_xcalloc_secure (size_t n, size_t m)
{ {
void *ret; void *ret;
ret = grub_zalloc (n * m); size_t sz;
if (grub_mul (n, m, &sz))
grub_fatal ("gcry_xcalloc would overflow");
ret = grub_zalloc (sz);
if (!ret) if (!ret)
grub_fatal ("gcry_xcalloc failed"); grub_fatal ("gcry_xcalloc failed");
return ret; return ret;

View file

@ -21,6 +21,7 @@
#include <grub/mm.h> #include <grub/mm.h>
#include <grub/misc.h> #include <grub/misc.h>
#include <grub/safemath.h>
static inline void static inline void
free (void *ptr) free (void *ptr)
@ -37,7 +38,12 @@ malloc (grub_size_t size)
static inline void * static inline void *
calloc (grub_size_t size, grub_size_t nelem) calloc (grub_size_t size, grub_size_t nelem)
{ {
return grub_zalloc (size * nelem); grub_size_t sz;
if (grub_mul (size, nelem, &sz))
return NULL;
return grub_zalloc (sz);
} }
static inline void * static inline void *

View file

@ -47,6 +47,7 @@ grub_util_device_is_mapped (const char *dev);
#define GRUB_HOST_PRIuLONG_LONG "llu" #define GRUB_HOST_PRIuLONG_LONG "llu"
#define GRUB_HOST_PRIxLONG_LONG "llx" #define GRUB_HOST_PRIxLONG_LONG "llx"
void * EXPORT_FUNC(xcalloc) (grub_size_t nmemb, grub_size_t size) WARN_UNUSED_RESULT;
void * EXPORT_FUNC(xmalloc) (grub_size_t size) WARN_UNUSED_RESULT; void * EXPORT_FUNC(xmalloc) (grub_size_t size) WARN_UNUSED_RESULT;
void * EXPORT_FUNC(xrealloc) (void *ptr, grub_size_t size) WARN_UNUSED_RESULT; void * EXPORT_FUNC(xrealloc) (void *ptr, grub_size_t size) WARN_UNUSED_RESULT;
char * EXPORT_FUNC(xstrdup) (const char *str) WARN_UNUSED_RESULT; char * EXPORT_FUNC(xstrdup) (const char *str) WARN_UNUSED_RESULT;

View file

@ -29,6 +29,7 @@
#endif #endif
void grub_mm_init_region (void *addr, grub_size_t size); void grub_mm_init_region (void *addr, grub_size_t size);
void *EXPORT_FUNC(grub_calloc) (grub_size_t nmemb, grub_size_t size);
void *EXPORT_FUNC(grub_malloc) (grub_size_t size); void *EXPORT_FUNC(grub_malloc) (grub_size_t size);
void *EXPORT_FUNC(grub_zalloc) (grub_size_t size); void *EXPORT_FUNC(grub_zalloc) (grub_size_t size);
void EXPORT_FUNC(grub_free) (void *ptr); void EXPORT_FUNC(grub_free) (void *ptr);
@ -48,6 +49,9 @@ extern int EXPORT_VAR(grub_mm_debug);
void grub_mm_dump_free (void); void grub_mm_dump_free (void);
void grub_mm_dump (unsigned lineno); void grub_mm_dump (unsigned lineno);
#define grub_calloc(nmemb, size) \
grub_debug_calloc (GRUB_FILE, __LINE__, nmemb, size)
#define grub_malloc(size) \ #define grub_malloc(size) \
grub_debug_malloc (GRUB_FILE, __LINE__, size) grub_debug_malloc (GRUB_FILE, __LINE__, size)
@ -63,6 +67,8 @@ void grub_mm_dump (unsigned lineno);
#define grub_free(ptr) \ #define grub_free(ptr) \
grub_debug_free (GRUB_FILE, __LINE__, ptr) grub_debug_free (GRUB_FILE, __LINE__, ptr)
void *EXPORT_FUNC(grub_debug_calloc) (const char *file, int line,
grub_size_t nmemb, grub_size_t size);
void *EXPORT_FUNC(grub_debug_malloc) (const char *file, int line, void *EXPORT_FUNC(grub_debug_malloc) (const char *file, int line,
grub_size_t size); grub_size_t size);
void *EXPORT_FUNC(grub_debug_zalloc) (const char *file, int line, void *EXPORT_FUNC(grub_debug_zalloc) (const char *file, int line,