]> git.saurik.com Git - apple/libc.git/blobdiff - stdio/FreeBSD/vfprintf.c
Libc-1439.100.3.tar.gz
[apple/libc.git] / stdio / FreeBSD / vfprintf.c
index 701e2ab9934963351c898254aaae52efe112127b..cf5104506df93638cee04ff3458c85d897143436 100644 (file)
  * SUCH DAMAGE.
  */
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wint-conversion"
+
+#include <TargetConditionals.h>
+#if !TARGET_OS_DRIVERKIT
+#define OS_CRASH_ENABLE_EXPERIMENTAL_LIBTRACE 1
+#endif
+
 #if defined(LIBC_SCCS) && !defined(lint)
 static char sccsid[] = "@(#)vfprintf.c 8.1 (Berkeley) 6/4/93";
 #endif /* LIBC_SCCS and not lint */
@@ -64,6 +72,10 @@ __FBSDID("$FreeBSD: src/lib/libc/stdio/vfprintf.c,v 1.90 2009/02/28 06:06:57 das
 #include <stdarg.h>
 #include "un-namespace.h"
 
+#include <os/assumes.h>
+#include <mach-o/dyld_priv.h>
+#include <mach/vm_region.h>
+
 #include "libc_private.h"
 #include "local.h"
 #include "fvwrite.h"
@@ -308,6 +320,26 @@ vfprintf(FILE * __restrict fp, const char * __restrict fmt0, va_list ap)
 #error "BUF must be large enough to format a uintmax_t"
 #endif
 
+__private_extern__ bool
+__printf_is_memory_read_only(void *addr, size_t __unused size)
+{
+       vm_address_t address = addr;
+       vm_size_t vmsize = 0;
+       vm_region_basic_info_data_64_t info;
+       mach_msg_type_number_t info_cnt = VM_REGION_BASIC_INFO_COUNT_64;
+       memory_object_name_t object = MACH_PORT_NULL;
+       kern_return_t kr = KERN_SUCCESS;
+
+       kr = vm_region_64(mach_task_self(),
+                       &address,
+                       &vmsize,
+                       VM_REGION_BASIC_INFO_64,
+                       (vm_region_info_t) &info,
+                       &info_cnt,
+                       &object);
+       return (kr == KERN_SUCCESS) && !(info.protection & VM_PROT_WRITE);
+}
+
 /*
  * Non-MT-safe version
  */
@@ -316,15 +348,19 @@ __vfprintf(FILE *fp, locale_t loc, const char *fmt0, va_list ap)
 {
        char *fmt;              /* format string */
        int ch;                 /* character from fmt */
-       int n, n2;              /* handy integer (short term usage) */
+       ssize_t n, n2;          /* handy integer (short term usage) */
        char *cp;               /* handy char pointer (short term usage) */
        int flags;              /* flags as above */
-       int ret;                /* return value accumulator */
-       int width;              /* width from format (%8d), or 0 */
-       int prec;               /* precision from format; <0 for N/A */
+       ssize_t ret;            /* return value accumulator */
+       ssize_t width;          /* width from format (%8d), or 0 */
+       ssize_t prec;           /* precision from format; <0 for N/A */
        char sign;              /* sign prefix (' ', '+', '-', or \0) */
        struct grouping_state gs; /* thousands' grouping info */
 
+#ifndef ALLOW_DYNAMIC_PERCENT_N
+       bool static_format_checked = false;
+#endif // ALLOW_DYNAMIC_PERCENT_N
+
 #ifndef NO_FLOATING_POINT
        /*
         * We can decompose the printed representation of floating
@@ -364,9 +400,9 @@ __vfprintf(FILE *fp, locale_t loc, const char *fmt0, va_list ap)
        uintmax_t ujval;        /* %j, %ll, %q, %t, %z integers */
        int base;               /* base for [diouxX] conversion */
        int dprec;              /* a copy of prec if [diouxX], 0 otherwise */
-       int realsz;             /* field size expanded by dprec, sign, etc */
-       int size;               /* size of converted field or string */
-       int prsize;             /* max size of printed field */
+       ssize_t realsz;         /* field size expanded by dprec, sign, etc */
+       ssize_t size;           /* size of converted field or string */
+       ssize_t prsize;             /* max size of printed field */
        const char *xdigs;      /* digits for %[xX] conversion */
        struct io_state io;     /* I/O buffering state */
        char buf[BUF];          /* buffer with space for digits of uintmax_t */
@@ -492,8 +528,9 @@ __vfprintf(FILE *fp, locale_t loc, const char *fmt0, va_list ap)
                for (cp = fmt; (ch = *fmt) != '\0' && ch != '%'; fmt++)
                        /* void */;
                if ((n = fmt - cp) != 0) {
-                       if ((unsigned)ret + n > INT_MAX) {
+                       if (ret + n >= INT_MAX) {
                                ret = EOF;
+                               errno = EOVERFLOW;
                                goto error;
                        }
                        PRINT(cp, n);
@@ -833,7 +870,21 @@ fp_common:
                        void *ptr = GETARG(void *);
                        if (ptr == NULL)
                                continue;
-                       else if (flags & LLONGINT)
+
+#ifndef ALLOW_DYNAMIC_PERCENT_N
+                       if (!static_format_checked) {
+                               static_format_checked = __printf_is_memory_read_only((void*)fmt0, strlen(fmt0));
+                       }
+                       if (!static_format_checked) {
+#if OS_CRASH_ENABLE_EXPERIMENTAL_LIBTRACE
+                               os_crash("%%n used in a non-immutable format string: %s", fmt0);
+#else
+                               os_crash("%%n used in a non-immutable format string");
+#endif
+                       }
+#endif // ALLOW_DYNAMIC_PERCENT_N
+
+                       if (flags & LLONGINT)
                                *(long long *)ptr = ret;
                        else if (flags & SIZET)
                                *(ssize_t *)ptr = (ssize_t)ret;
@@ -904,7 +955,15 @@ fp_common:
                                }
                        } else if ((cp = GETARG(char *)) == NULL)
                                cp = "(null)";
-                       size = (prec >= 0) ? strnlen(cp, prec) : strlen(cp);
+                       {
+                               size_t cp_len = (prec >= 0) ? strnlen(cp, prec) : strlen(cp);
+                               if (cp_len < INT_MAX) {
+                                       size = cp_len;
+                               } else {
+                                       ret = EOF;
+                                       goto error;
+                               }
+                       }
                        sign = '\0';
                        break;
                case 'U':
@@ -976,7 +1035,7 @@ number:                    if ((dprec = prec) >= 0)
                        }
                        size = buf + BUF - cp;
                        if (size > BUF) /* should never happen */
-                               LIBC_ABORT("size (%d) > BUF (%d)", size, BUF);
+                               LIBC_ABORT("size (%zd) > BUF (%d)", size, BUF);
                        if ((flags & GROUPING) && size != 0)
                                size += grouping_init(&gs, size, loc);
                        break;
@@ -1301,8 +1360,9 @@ number:                   if ((dprec = prec) >= 0)
                        realsz += 2;
 
                prsize = width > realsz ? width : realsz;
-               if ((unsigned)ret + prsize > INT_MAX) {
+               if (ret + prsize >= INT_MAX) {
                        ret = EOF;
+                       errno = EOVERFLOW;
                        goto error;
                }
 
@@ -1395,7 +1455,7 @@ error:
                ret = EOF;
        if ((argtable != NULL) && (argtable != statargtable))
                free (argtable);
-       return (ret);
+       return (ret < 0 || ret >= INT_MAX) ? -1 : (int)ret;
        /* NOTREACHED */
 }
-
+#pragma clang diagnostic pop