[PATCH] Better overflow handling in rcstime.c

[Fritjof Bornebusch]

Hi tech,

remove the atoi calls, in order to avoid overflows.

fritjof


Index: rcstime.c
===================================================================
RCS file: /cvs/src/usr.bin/rcs/rcstime.c,v
retrieving revision 1.4
diff -u -p -r1.4 rcstime.c
--- rcstime.c   29 Apr 2014 07:44:19 -0000      1.4
+++ rcstime.c   30 Jun 2014 12:59:42 -0000
@@ -36,6 +36,7 @@ rcs_set_tz(char *tz, struct rcs_delta *r
        int tzone;
        int pos;
        char *h, *m;
+       const char *errstr = NULL;
        struct tm *ltb;
        time_t now;
 
@@ -62,8 +63,8 @@ rcs_set_tz(char *tz, struct rcs_delta *r
 
                memcpy(tb, &rdp->rd_date, sizeof(*tb));
 
-               tzone = atoi(h);
-               if ((tzone >= 24) || (tzone <= -24))
+               tzone = (int)strtonum(h, -23, 23, &errstr);
+               if (errstr)
                        errx(1, "%s: not a known time zone", tz);
 
                if (pos) {
@@ -78,9 +79,9 @@ rcs_set_tz(char *tz, struct rcs_delta *r
                        tb->tm_hour = 0;
 
                if (m != NULL) {
-                       tzone = atoi(m);
-                       if (tzone >= 60)
-                               errx(1, "%s: not a known time zone", tz);
+                       tzone = (int)strtonum(m, 0, 59, &errstr);
+                       if (errstr)
+                               errx(1, "%s: not a known minute", m);
 
                        if ((tb->tm_min + tzone) >= 60) {
                                tb->tm_hour++;