bin/42143: A transformation without the cast

[yasu1224%ics.nara-wu.ac.jp@localhost]

>Number:         42143
>Category:       bin
>Synopsis:       A transformation without the cast
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Oct 01 06:50:00 +0000 2009
>Originator:     Yamanishi Yasuyo
>Release:        i386
>Organization:
Nara Women's University
>Environment:
NetBSD ayanamirei 4.0 NetBSD 4.0 (GENERIC) #0: Sun Dec 16 00:20:10 PST 2007  
builds@wb34:/home/builds/ab/netbsd-4-0-RELEASE/i386/200712160005Z-obj/home/builds/ab/netbsd-4-0-RELEASE/src/sys/arch/i386/compile/GENERIC
 i386


>Description:
Implicit cast from long to int may cause an integer overflow
especially with 64-bit CPU.  A wrapper function can fix it.
>How-To-Repeat:

>Fix:
--- kill2.c     2009-09-30 23:58:53.000000000 +0900
+++ kill.c      2009-09-25 23:00:33.000000000 +0900
@@ -64,6 +64,7 @@
 static void printsignals(FILE *);
 static int signame_to_signum(char *);
 static void usage(void);
+static strto_int(const char*,char**,int);
 int main(int, char *[]);
 
 int
@@ -87,7 +88,7 @@
                if (argc == 1) {
                        if (isdigit((unsigned char)**argv) == 0)
                                usage();
-                       numsig = strtol(*argv, &ep, 10);
+                       numsig = strto_int(*argv, &ep, 10);
                        if (*ep != '\0') {
                                errx(EXIT_FAILURE, "illegal signal number: %s",
                                         *argv);
@@ -122,7 +123,7 @@
                        if ((numsig = signame_to_signum(sn)) < 0)
                                nosig(sn);
                } else if (isdigit((unsigned char)*sn)) {
-                       numsig = strtol(sn, &ep, 10);
+                       numsig = strto_int(sn, &ep, 10);
                        if (*ep) {
                                errx(EXIT_FAILURE, "illegal signal number: %s",
                                         sn);
@@ -151,7 +152,7 @@
                } else 
 #endif
                {
-                       pid = strtol(*argv, &ep, 10);
+                       pid = strto_int(*argv, &ep, 10);
                        if (!**argv || *ep) {
                                warnx("illegal process id: %s", *argv);
                                errors = 1;
@@ -240,4 +241,23 @@
                        getprogname(), getprogname(), getprogname(), 
getprogname());
        exit(1);
        /* NOTREACHED */
-}
\ No newline at end of file
+}
+
+static int 
+strto_int(const char * nptr ,char ** end ,int  base)
+{
+       int  tmp;
+       long sig,check;
+       
+       sig = strtol(nptr, end, base);
+       tmp = (int) sig;
+       check = (long) tmp;
+       
+       if( check != sig ){
+               warnx("Overflow occered in the cast (from long to int) .");
+       }
+       
+       return tmp;
+}
+
+