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Use sudo_mmap_alloc functions instead of private versions.

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We no longer need to keep track of the allocation size.
This commit is contained in:
Todd C. Miller
2022-07-25 16:05:10 -06:00
parent fccf3c9c56
commit e43c964c43
1 changed files with 13 additions and 57 deletions
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70
lib/util/snprintf.c
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@@ -47,8 +47,6 @@
!defined(HAVE_VASPRINTF) || !defined(HAVE_ASPRINTF) || \
defined(PREFER_PORTABLE_SNPRINTF)
#include <sys/mman.h>
#include <errno.h>
#ifdef HAVE_NL_LANGINFO
# include <langinfo.h>
@@ -71,6 +69,7 @@
#include <fcntl.h>
#include "sudo_compat.h"
#include "sudo_util.h"
/* Avoid printf format attacks by ignoring the %n escape. */
#define NO_PRINTF_PERCENT_N
@@ -107,51 +106,10 @@ union arg {
#endif
};
static int __find_arguments(const char *fmt0, va_list ap, union arg **argtable,
size_t *argtablesiz);
static int __find_arguments(const char *fmt0, va_list ap, union arg **argtable);
static int __grow_type_table(unsigned char **typetable, int *tablesize);
static int xxxprintf(char **, size_t, int, const char *, va_list);
#if !defined(MAP_ANON) && defined(MAP_ANONYMOUS)
# define MAP_ANON MAP_ANONYMOUS
#endif
#ifndef MAP_FAILED
# define MAP_FAILED ((void *) -1)
#endif
/*
* Allocate "size" bytes via mmap.
*/
static void *
mmap_alloc(size_t size)
{
void *p;
#ifndef MAP_ANON
int fd;
if ((fd = open("/dev/zero", O_RDWR)) == -1)
return NULL;
p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
close(fd);
#else
p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
#endif
if (p == MAP_FAILED)
return NULL;
return p;
}
/*
* Unmap "size" bytes of the ptr.
*/
static void
mmap_free(void *ptr, size_t size)
{
if (ptr != NULL)
munmap(ptr, size);
}
#ifdef PRINTF_WIDE_CHAR
/*
* Convert a wide character string argument for the %ls format to a multibyte
@@ -330,7 +288,6 @@ xxxprintf(char **strp, size_t strsize, int alloc, const char *fmt0, va_list ap)
char *estr; /* pointer to last char in str */
union arg *argtable; /* args, built due to positional arg */
union arg statargtable[STATIC_ARG_TBL_SIZE];
size_t argtablesiz;
int nextarg; /* 1-based argument index */
va_list orgap; /* original argument pointer */
#ifdef PRINTF_WIDE_CHAR
@@ -442,7 +399,7 @@ xxxprintf(char **strp, size_t strsize, int alloc, const char *fmt0, va_list ap)
int hold = nextarg; \
if (argtable == NULL) { \
argtable = statargtable; \
__find_arguments(fmt0, orgap, &argtable, &argtablesiz); \
__find_arguments(fmt0, orgap, &argtable); \
} \
nextarg = n2; \
val = GETARG(int); \
@@ -562,7 +519,7 @@ reswitch: switch (ch) {
if (argtable == NULL) {
argtable = statargtable;
__find_arguments(fmt0, orgap,
&argtable, &argtablesiz);
&argtable);
}
goto rflag;
}
@@ -588,7 +545,7 @@ reswitch: switch (ch) {
if (argtable == NULL) {
argtable = statargtable;
__find_arguments(fmt0, orgap,
&argtable, &argtablesiz);
&argtable);
}
goto rflag;
}
@@ -1076,7 +1033,7 @@ finish:
__freedtoa(dtoaresult);
#endif
if (argtable != NULL && argtable != statargtable) {
mmap_free(argtable, argtablesiz);
sudo_mmap_free(argtable);
argtable = NULL;
}
return ret;
@@ -1124,8 +1081,7 @@ finish:
* problematic since we have nested functions..)
*/
static int
__find_arguments(const char *fmt0, va_list ap, union arg **argtable,
size_t *argtablesiz)
__find_arguments(const char *fmt0, va_list ap, union arg **argtable)
{
char *fmt; /* format string */
int ch; /* character from fmt */
@@ -1354,8 +1310,8 @@ done:
* Build the argument table.
*/
if (tablemax >= STATIC_ARG_TBL_SIZE) {
*argtablesiz = sizeof(union arg) * (tablemax + 1);
*argtable = mmap_alloc(*argtablesiz);
*argtable = sudo_mmap_allocarray(tablemax + 1,
sizeof(union arg));
if (*argtable == NULL)
return -1;
}
@@ -1453,7 +1409,7 @@ overflow:
finish:
if (typetable != NULL && typetable != stattypetable) {
mmap_free(typetable, *argtablesiz);
sudo_mmap_free(typetable);
typetable = NULL;
}
return ret;
@@ -1472,16 +1428,16 @@ __grow_type_table(unsigned char **typetable, int *tablesize)
newsize = sysconf(_SC_PAGESIZE);
if (*tablesize == STATIC_ARG_TBL_SIZE) {
*typetable = mmap_alloc(newsize);
*typetable = sudo_mmap_alloc(newsize);
if (*typetable == NULL)
return -1;
memcpy(*typetable, oldtable, *tablesize);
} else {
unsigned char *new = mmap_alloc(newsize);
unsigned char *new = sudo_mmap_alloc(newsize);
if (new == NULL)
return -1;
memmove(new, *typetable, *tablesize);
mmap_free(*typetable, *tablesize);
sudo_mmap_free(*typetable);
*typetable = new;
}
memset(*typetable + *tablesize, T_UNUSED, (newsize - *tablesize));