From: Ondřej Surý <ondrej@isc.org>
Date: Thu, 14 Jul 2022 11:48:45 +0000 (+0200)
Subject: Increase the BUFSIZ-long buffers
X-Git-Tag: v9.19.4~22^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b35861f1eb8f76e70bea84ff49c38616d83bf5cf;p=thirdparty%2Fbind9.git

Increase the BUFSIZ-long buffers

The BUFSIZ value varies between platforms, it could be 8K on Linux and
512 bytes on mingw.  Make sure the buffers are always big enough for the
output data to prevent truncation of the output by appropriately
enlarging or sizing the buffers.
---

diff --git a/bin/named/server.c b/bin/named/server.c
index d28926914e5..7c2499ea2ae 100644
--- a/bin/named/server.c
+++ b/bin/named/server.c
@@ -14921,7 +14921,12 @@ named_server_signing(named_server_t *server, isc_lex_t *lex,
 		     result = dns_rdataset_next(&privset))
 		{
 			dns_rdata_t priv = DNS_RDATA_INIT;
-			char output[BUFSIZ];
+			/*
+			 * In theory, the output buffer could hold a full RDATA
+			 * record which is 16-bit and then some text around
+			 * it
+			 */
+			char output[UINT16_MAX + BUFSIZ];
 			isc_buffer_t buf;
 
 			dns_rdataset_current(&privset, &priv);
diff --git a/bin/tests/system/feature-test.c b/bin/tests/system/feature-test.c
index 30e6e14575e..3435c91e07f 100644
--- a/bin/tests/system/feature-test.c
+++ b/bin/tests/system/feature-test.c
@@ -11,6 +11,7 @@
  * information regarding copyright ownership.
  */
 
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -22,14 +23,6 @@
 
 #include <dns/edns.h>
 
-#ifndef MAXHOSTNAMELEN
-#ifdef HOST_NAME_MAX
-#define MAXHOSTNAMELEN HOST_NAME_MAX
-#else /* ifdef HOST_NAME_MAX */
-#define MAXHOSTNAMELEN 256
-#endif /* ifdef HOST_NAME_MAX */
-#endif /* ifndef MAXHOSTNAMELEN */
-
 static void
 usage(void) {
 	fprintf(stderr, "usage: feature-test <arg>\n");
@@ -91,7 +84,7 @@ main(int argc, char **argv) {
 	}
 
 	if (strcmp(argv[1], "--gethostname") == 0) {
-		char hostname[MAXHOSTNAMELEN];
+		char hostname[_POSIX_HOST_NAME_MAX + 1];
 		int n;
 
 		n = gethostname(hostname, sizeof(hostname));
diff --git a/lib/dns/adb.c b/lib/dns/adb.c
index b97f3e63905..3ff149a7740 100644
--- a/lib/dns/adb.c
+++ b/lib/dns/adb.c
@@ -3010,7 +3010,7 @@ dns_adb_dumpquota(dns_adb_t *adb, isc_buffer_t **buf) {
 		     entry = ISC_LIST_NEXT(entry, plink))
 		{
 			char addrbuf[ISC_NETADDR_FORMATSIZE];
-			char text[BUFSIZ];
+			char text[ISC_NETADDR_FORMATSIZE + BUFSIZ];
 			isc_netaddr_t netaddr;
 
 			if (entry->atr == 0.0 && entry->quota == adb->quota) {
diff --git a/lib/dns/private.c b/lib/dns/private.c
index 58deda095a9..cbf947f8ccc 100644
--- a/lib/dns/private.c
+++ b/lib/dns/private.c
@@ -383,7 +383,8 @@ dns_private_totext(dns_rdata_t *private, isc_buffer_t *buf) {
 	} else if (private->length == 5) {
 		unsigned char alg = private->data[0];
 		dns_keytag_t keyid = (private->data[2] | private->data[1] << 8);
-		char keybuf[BUFSIZ], algbuf[DNS_SECALG_FORMATSIZE];
+		char keybuf[DNS_SECALG_FORMATSIZE + BUFSIZ],
+			algbuf[DNS_SECALG_FORMATSIZE];
 		bool del = private->data[3];
 		bool complete = private->data[4];
 
diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index ddc0ed50419..7fa7040aa2c 100644
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -11538,7 +11538,8 @@ dns_resolver_dumpquota(dns_resolver_t *res, isc_buffer_t **buf) {
 		for (fctxcount_t *fc = ISC_LIST_HEAD(bucket->list); fc != NULL;
 		     fc = ISC_LIST_NEXT(fc, link))
 		{
-			char nb[DNS_NAME_FORMATSIZE], text[BUFSIZ];
+			char nb[DNS_NAME_FORMATSIZE],
+				text[DNS_NAME_FORMATSIZE + BUFSIZ];
 
 			if (fc->count < spill) {
 				continue;
diff --git a/lib/ns/client.c b/lib/ns/client.c
index 836cedc8e1a..436cc19a89c 100644
--- a/lib/ns/client.c
+++ b/lib/ns/client.c
@@ -12,6 +12,7 @@
  */
 
 #include <inttypes.h>
+#include <limits.h>
 #include <stdbool.h>
 
 #include <isc/aes.h>
@@ -955,7 +956,7 @@ isc_result_t
 ns_client_addopt(ns_client_t *client, dns_message_t *message,
 		 dns_rdataset_t **opt) {
 	unsigned char ecs[ECS_SIZE];
-	char nsid[BUFSIZ], *nsidp = NULL;
+	char nsid[_POSIX_HOST_NAME_MAX + 1], *nsidp = NULL;
 	unsigned char cookie[COOKIE_SIZE];
 	isc_result_t result;
 	dns_view_t *view = NULL;