check for integer overflows in custom allocs, okay jca@

diff --git a/usr.bin/m4/eval.c b/usr.bin/m4/eval.c
index a145c10..a11895e 100644 (file)
--- a/usr.bin/m4/eval.c
+++ b/usr.bin/m4/eval.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: eval.c,v 1.71 2013/11/14 15:56:50 deraadt Exp $       */
+/*     $OpenBSD: eval.c,v 1.72 2014/04/28 12:34:11 espie Exp $ */
 /*     $NetBSD: eval.c,v 1.7 1996/11/10 21:21:29 pk Exp $      */
 
 /*
@@ -790,7 +790,7 @@ dom4wrap(const char *text)
                        maxwraps = 16;
                else
                        maxwraps *= 2;
-               m4wraps = xrealloc(m4wraps, maxwraps * sizeof(*m4wraps),
+               m4wraps = xreallocarray(m4wraps, maxwraps, sizeof(*m4wraps),
                   "too many m4wraps");
        }
        m4wraps[wrapindex++] = xstrdup(text);

diff --git a/usr.bin/m4/extern.h b/usr.bin/m4/extern.h
index ef59ad7..38a9635 100644 (file)
--- a/usr.bin/m4/extern.h
+++ b/usr.bin/m4/extern.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: extern.h,v 1.52 2012/04/12 17:00:11 espie Exp $       */
+/*     $OpenBSD: extern.h,v 1.53 2014/04/28 12:34:11 espie Exp $       */
 /*     $NetBSD: extern.h,v 1.3 1996/01/13 23:25:24 pk Exp $    */
 
 /*-
@@ -102,8 +102,10 @@ extern void        pbnumbase(int, int, int);
 extern void    pbunsigned(unsigned long);
 extern void    pbstr(const char *);
 extern void    pushback(int);
-extern void    *xalloc(size_t, const char *fmt, ...);
-extern void    *xrealloc(void *, size_t, const char *fmt, ...);
+extern void    *xalloc(size_t, const char *, ...);
+extern void    *xallocarray(size_t, size_t, const char *, ...);
+extern void    *xrealloc(void *, size_t, const char *, ...);
+extern void    *xreallocarray(void *, size_t, size_t, const char *, ...);
 extern char    *xstrdup(const char *);
 extern void    usage(void);
 extern void    resizedivs(int);

diff --git a/usr.bin/m4/gnum4.c b/usr.bin/m4/gnum4.c
index a107033..9d6621e 100644 (file)
--- a/usr.bin/m4/gnum4.c
+++ b/usr.bin/m4/gnum4.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gnum4.c,v 1.43 2013/11/20 16:44:27 deraadt Exp $ */
+/* $OpenBSD: gnum4.c,v 1.44 2014/04/28 12:34:11 espie Exp $ */
 
 /*
  * Copyright (c) 1999 Marc Espie
@@ -469,7 +469,7 @@ dopatsubst(const char *argv[], int argc)
                if (error != 0)
                        exit_regerror(error, &re);
 
-               pmatch = xalloc(sizeof(regmatch_t) * (re.re_nsub+1), NULL);
+               pmatch = xallocarray(re.re_nsub+1, sizeof(regmatch_t), NULL);
                do_subst(argv[2], &re,
                    argc > 4 && argv[4] != NULL ? argv[4] : "", pmatch);
                free(pmatch);
@@ -501,7 +501,7 @@ doregexp(const char *argv[], int argc)
        if (error != 0)
                exit_regerror(error, &re);
 
-       pmatch = xalloc(sizeof(regmatch_t) * (re.re_nsub+1), NULL);
+       pmatch = xallocarray(re.re_nsub+1, sizeof(regmatch_t), NULL);
        if (argc == 4 || argv[4] == NULL)
                do_regexpindex(argv[2], &re, pmatch);
        else

diff --git a/usr.bin/m4/main.c b/usr.bin/m4/main.c
index 4c5af0a..dc2b9e5 100644 (file)
--- a/usr.bin/m4/main.c
+++ b/usr.bin/m4/main.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: main.c,v 1.81 2012/04/12 17:00:11 espie Exp $ */
+/*     $OpenBSD: main.c,v 1.82 2014/04/28 12:34:11 espie Exp $ */
 /*     $NetBSD: main.c,v 1.12 1997/02/08 23:54:49 cgd Exp $    */
 
 /*-
@@ -181,8 +181,8 @@ main(int argc, char *argv[])
        initspaces();
        STACKMAX = INITSTACKMAX;
 
-       mstack = (stae *)xalloc(sizeof(stae) * STACKMAX, NULL);
-       sstack = (char *)xalloc(STACKMAX, NULL);
+       mstack = xallocarray(STACKMAX, sizeof(stae), NULL);
+       sstack = xalloc(STACKMAX, NULL);
 
        maxout = 0;
        outfile = NULL;
@@ -626,7 +626,7 @@ static void
 enlarge_stack(void)
 {
        STACKMAX += STACKMAX/2;
-       mstack = xrealloc(mstack, sizeof(stae) * STACKMAX,
+       mstack = xreallocarray(mstack, STACKMAX, sizeof(stae),
            "Evaluation stack overflow (%lu)",
            (unsigned long)STACKMAX);
        sstack = xrealloc(sstack, STACKMAX,

diff --git a/usr.bin/m4/misc.c b/usr.bin/m4/misc.c
index 80cdb47..16697a4 100644 (file)
--- a/usr.bin/m4/misc.c
+++ b/usr.bin/m4/misc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: misc.c,v 1.42 2010/09/07 19:58:09 marco Exp $ */
+/*     $OpenBSD: misc.c,v 1.43 2014/04/28 12:34:11 espie Exp $ */
 /*     $NetBSD: misc.c,v 1.6 1995/09/28 05:37:41 tls Exp $     */
 
 /*
@@ -38,6 +38,7 @@
 #include <unistd.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <stddef.h>
 #include <string.h>
@@ -163,7 +164,7 @@ initspaces()
        strspace = xalloc(strsize+1, NULL);
        ep = strspace;
        endest = strspace+strsize;
-       buf = (unsigned char *)xalloc(bufsize, NULL);
+       buf = xalloc(bufsize, NULL);
        bufbase = buf;
        bp = buf;
        endpbb = buf + bufsize;
@@ -283,7 +284,7 @@ resizedivs(int n)
 {
        int i;
 
-       outfile = (FILE **)xrealloc(outfile, sizeof(FILE *) * n,
+       outfile = xreallocarray(outfile, n, sizeof(FILE *),
            "too many diverts %d", n);
        for (i = maxout; i < n; i++)
                outfile[i] = NULL;
@@ -309,6 +310,32 @@ xalloc(size_t n, const char *fmt, ...)
        return p;
 }
 
+void *
+xallocarray(size_t s1, size_t s2, const char *fmt, ...)
+{
+       void *p;
+
+       if (s1 && SIZE_MAX / s1 < s2) {
+               errno = ENOMEM;
+               p = NULL;
+       } else {
+               p = malloc(s1 * s2);
+       }
+
+       if (p == NULL) {
+               if (fmt == NULL)
+                       err(1, "malloc");
+               else {
+                       va_list va;
+
+                       va_start(va, fmt);
+                       verr(1, fmt, va);
+                       va_end(va);
+               }
+       }
+       return p;
+}
+
 void *
 xrealloc(void *old, size_t n, const char *fmt, ...)
 {
@@ -329,6 +356,33 @@ xrealloc(void *old, size_t n, const char *fmt, ...)
        return p;
 }
 
+void *
+xreallocarray(void *old, size_t s1, size_t s2, const char *fmt, ...)
+{
+       void *p;
+
+       if (s1 && SIZE_MAX / s1 < s2) {
+               errno = ENOMEM;
+               p = NULL;
+       } else {
+               p = realloc(old, s1 * s2);
+       }
+
+       if (p == NULL) {
+               free(old);
+               if (fmt == NULL)
+                       err(1, "realloc");
+               else {
+                       va_list va;
+
+                       va_start(va, fmt);
+                       verr(1, fmt, va);
+                       va_end(va);
+               }
+       }
+       return p;
+}
+
 char *
 xstrdup(const char *s)
 {