Replace atoi with strtonum for stricter and safer integer parsing.

-N ndots: 0, INT_MAX
The upper limit is a bit silly, everything bigger than a small number
will force domain names to be interpretet as relative.

-R retries INT_MIN, INT_MAX - 1
Specifically documented to accept negative numbers.

-W wait 0, INT_MAX
One could interpret the documentation as meaning that it accepts
negative numbers but that failes later on with an error message from
the timer code..

with deraadt, OK kn, input & OK tedu

1 files changed, 15 insertions, 9 deletions

diff --git a/usr.sbin/bind/bin/dig/host.c b/usr.sbin/bind/bin/dig/host.c
index 227bf11d168..085b0f32366 100644
--- a/usr.sbin/bind/bin/dig/host.c
+++ b/usr.sbin/bind/bin/dig/host.c
@@ -17,20 +17,18 @@
 /*! \file */
 #include <sys/cdefs.h>
 
-#include <stdlib.h>
-#include <unistd.h>
+#include <err.h>
 #include <limits.h>
-
 #include <locale.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 #include <isc/app.h>
 #include <isc/netaddr.h>
-
-#include <string.h>
 #include <isc/util.h>
 #include <isc/task.h>
 
-
 #include <dns/byaddr.h>
 #include <dns/fixedname.h>
 #include <dns/message.h>
@@ -628,6 +626,7 @@ parse_args(int argc, char **argv) {
 	dns_rdatatype_t rdtype;
 	dns_rdataclass_t rdclass;
 	uint32_t serial = 0;
+	const char *errstr;
 
 	lookup = make_empty_lookup();
 
@@ -727,12 +726,17 @@ parse_args(int argc, char **argv) {
 			timeout = INT_MAX;
 			break;
 		case 'W':
-			timeout = atoi(optarg);
+			timeout = strtonum(optarg, 0, INT_MAX, &errstr);
+			if (errstr != NULL)
+				errx(1, "timeout is %s: %s", errstr, optarg);
 			if (timeout < 1)
 				timeout = 1;
 			break;
 		case 'R':
-			tries = atoi(optarg) + 1;
+			tries = strtonum(optarg, INT_MIN, INT_MAX - 1, &errstr);
+			if (errstr != NULL)
+				errx(1, "retries is %s: %s", errstr, optarg);
+			tries++;
 			if (tries < 2)
 				tries = 2;
 			break;
@@ -752,7 +756,9 @@ parse_args(int argc, char **argv) {
 			break;
 		case 'N':
 			debug("setting NDOTS to %s", optarg);
-			ndots = atoi(optarg);
+			ndots = strtonum(optarg, 0, INT_MAX, &errstr);
+			if (errstr != NULL)
+				errx(1, "ndots is %s: %s", errstr, optarg);
 			break;
 		case 'D':
 			/* Handled by pre_parse_args(). */