commit a71a3374cd8cf53776c33994f69ec184c26f2129
Author: Florian Weimer <fweimer@redhat.com>
Date: Mon Sep 4 11:27:24 2017 +0200
getaddrinfo: Fix error handling in gethosts [BZ #21915] [BZ #21922]
The old code uses errno as the primary indicator for success or
failure. This is wrong because errno is only set for specific
combinations of the status return value and the h_errno variable.
(cherry picked from commit f4a6be2582b8dfe8adfa68da3dd8decf566b3983)
diff --git a/nss/Makefile b/nss/Makefile
index f0a6e4877fac6bf7..a6e994aa9f6df0bc 100644
--- a/nss/Makefile
+++ b/nss/Makefile
@@ -54,6 +54,11 @@ tests = test-netdb tst-nss-test1 test-digits-dots \
$(tests-static)
xtests = bug-erange
+# Tests which need libdl
+ifeq (yes,$(build-shared))
+tests += tst-nss-files-hosts-erange
+endif
+
# If we have a thread library then we can test cancellation against
# some routines like getpwuid_r.
ifeq (yes,$(have-thread-library))
@@ -139,3 +144,5 @@ $(objpfx)tst-nss-test1.out: $(objpfx)/libnss_test1.so$(libnss_test1.so-version)
ifeq (yes,$(have-thread-library))
$(objpfx)tst-cancel-getpwuid_r: $(shared-thread-library)
endif
+
+$(objpfx)tst-nss-files-hosts-erange: $(libdl)
diff --git a/nss/tst-nss-files-hosts-erange.c b/nss/tst-nss-files-hosts-erange.c
new file mode 100644
index 0000000000000000..beb7aa9fa0b5926f
--- /dev/null
+++ b/nss/tst-nss-files-hosts-erange.c
@@ -0,0 +1,109 @@
+/* Parse /etc/hosts in multi mode with a trailing long line (bug 21915).
+ Copyright (C) 2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+
+#include <dlfcn.h>
+#include <errno.h>
+#include <gnu/lib-names.h>
+#include <netdb.h>
+#include <nss.h>
+#include <support/check.h>
+#include <support/check_nss.h>
+#include <support/namespace.h>
+#include <support/test-driver.h>
+#include <support/xunistd.h>
+
+struct support_chroot *chroot_env;
+
+#define X10 "XXXXXXXXXX"
+#define X100 X10 X10 X10 X10 X10 X10 X10 X10 X10 X10
+#define X1000 X100 X100 X100 X100 X100 X100 X100 X100 X100 X100
+
+static void
+prepare (int argc, char **argv)
+{
+ chroot_env = support_chroot_create
+ ((struct support_chroot_configuration)
+ {
+ .resolv_conf = "",
+ .hosts =
+ "127.0.0.1 localhost localhost.localdomain\n"
+ "::1 localhost localhost.localdomain\n"
+ "192.0.2.1 example.com\n"
+ "#" X1000 X100 "\n",
+ .host_conf = "multi on\n",
+ });
+}
+
+static int
+do_test (void)
+{
+ support_become_root ();
+ if (!support_can_chroot ())
+ return EXIT_UNSUPPORTED;
+
+ __nss_configure_lookup ("hosts", "files");
+ if (dlopen (LIBNSS_FILES_SO, RTLD_LAZY) == NULL)
+ FAIL_EXIT1 ("could not load " LIBNSS_DNS_SO ": %s", dlerror ());
+
+ xchroot (chroot_env->path_chroot);
+
+ errno = ERANGE;
+ h_errno = NETDB_INTERNAL;
+ check_hostent ("gethostbyname example.com",
+ gethostbyname ("example.com"),
+ "name: example.com\n"
+ "address: 192.0.2.1\n");
+ errno = ERANGE;
+ h_errno = NETDB_INTERNAL;
+ check_hostent ("gethostbyname2 AF_INET example.com",
+ gethostbyname2 ("example.com", AF_INET),
+ "name: example.com\n"
+ "address: 192.0.2.1\n");
+ {
+ struct addrinfo hints =
+ {
+ .ai_family = AF_UNSPEC,
+ .ai_socktype = SOCK_STREAM,
+ .ai_protocol = IPPROTO_TCP,
+ };
+ errno = ERANGE;
+ h_errno = NETDB_INTERNAL;
+ struct addrinfo *ai;
+ int ret = getaddrinfo ("example.com", "80", &hints, &ai);
+ check_addrinfo ("example.com AF_UNSPEC", ai, ret,
+ "address: STREAM/TCP 192.0.2.1 80\n");
+ if (ret == 0)
+ freeaddrinfo (ai);
+
+ hints.ai_family = AF_INET;
+ errno = ERANGE;
+ h_errno = NETDB_INTERNAL;
+ ret = getaddrinfo ("example.com", "80", &hints, &ai);
+ check_addrinfo ("example.com AF_INET", ai, ret,
+ "address: STREAM/TCP 192.0.2.1 80\n");
+ if (ret == 0)
+ freeaddrinfo (ai);
+ }
+
+ support_chroot_free (chroot_env);
+ return 0;
+}
+
+#define PREPARE prepare
+#include <support/test-driver.c>
diff --git a/resolv/tst-resolv-basic.c b/resolv/tst-resolv-basic.c
index 64eedbbd81d58d95..66a0e8a1659219b4 100644
--- a/resolv/tst-resolv-basic.c
+++ b/resolv/tst-resolv-basic.c
@@ -50,7 +50,7 @@ response (const struct resolv_response_context *ctx,
qname_compare = qname + 2;
else
qname_compare = qname;
- enum {www, alias, nxdomain, long_name} requested_qname;
+ enum {www, alias, nxdomain, long_name, nodata} requested_qname;
if (strcmp (qname_compare, "www.example") == 0)
requested_qname = www;
else if (strcmp (qname_compare, "alias.example") == 0)
@@ -59,6 +59,8 @@ response (const struct resolv_response_context *ctx,
requested_qname = nxdomain;
else if (strcmp (qname_compare, LONG_NAME) == 0)
requested_qname = long_name;
+ else if (strcmp (qname_compare, "nodata.example") == 0)
+ requested_qname = nodata;
else
{
support_record_failure ();
@@ -87,6 +89,8 @@ response (const struct resolv_response_context *ctx,
resolv_response_close_record (b);
resolv_response_open_record (b, "www.example", qclass, qtype, 0);
break;
+ case nodata:
+ return;
case nxdomain:
FAIL_EXIT1 ("unreachable");
}
@@ -267,6 +271,55 @@ test_bug_21295 (void)
}
}
+/* Run tests which do not expect any data. */
+static void
+test_nodata_nxdomain (void)
+{
+ /* Iterate through different address families. */
+ int families[] = { AF_UNSPEC, AF_INET, AF_INET6, -1 };
+ for (int i = 0; families[i] >= 0; ++i)
+ /* If do_tcp, prepend "t." to the name to trigger TCP
+ fallback. */
+ for (int do_tcp = 0; do_tcp < 2; ++do_tcp)
+ /* If do_nxdomain, trigger an NXDOMAIN error (DNS failure),
+ otherwise use a NODATA response (empty but successful
+ answer). */
+ for (int do_nxdomain = 0; do_nxdomain < 2; ++do_nxdomain)
+ {
+ int family = families[i];
+ char *name = xasprintf ("%s%s.example",
+ do_tcp ? "t." : "",
+ do_nxdomain ? "nxdomain" : "nodata");
+
+ if (family != AF_UNSPEC)
+ {
+ if (do_nxdomain)
+ check_h (name, family, "error: HOST_NOT_FOUND\n");
+ else
+ check_h (name, family, "error: NO_ADDRESS\n");
+ }
+
+ const char *expected;
+ if (do_nxdomain)
+ expected = "error: Name or service not known\n";
+ else
+ expected = "error: No address associated with hostname\n";
+
+ check_ai (name, "80", family, expected);
+
+ struct addrinfo hints =
+ {
+ .ai_family = family,
+ .ai_flags = AI_V4MAPPED | AI_ALL,
+ };
+ check_ai_hints (name, "80", hints, expected);
+ hints.ai_flags |= AI_CANONNAME;
+ check_ai_hints (name, "80", hints, expected);
+
+ free (name);
+ }
+}
+
static int
do_test (void)
{
@@ -439,29 +492,8 @@ do_test (void)
"address: DGRAM/UDP 2001:db8::4 80\n"
"address: RAW/IP 2001:db8::4 80\n");
- check_h ("nxdomain.example", AF_INET,
- "error: HOST_NOT_FOUND\n");
- check_h ("nxdomain.example", AF_INET6,
- "error: HOST_NOT_FOUND\n");
- check_ai ("nxdomain.example", "80", AF_UNSPEC,
- "error: Name or service not known\n");
- check_ai ("nxdomain.example", "80", AF_INET,
- "error: Name or service not known\n");
- check_ai ("nxdomain.example", "80", AF_INET6,
- "error: Name or service not known\n");
-
- check_h ("t.nxdomain.example", AF_INET,
- "error: HOST_NOT_FOUND\n");
- check_h ("t.nxdomain.example", AF_INET6,
- "error: HOST_NOT_FOUND\n");
- check_ai ("t.nxdomain.example", "80", AF_UNSPEC,
- "error: Name or service not known\n");
- check_ai ("t.nxdomain.example", "80", AF_INET,
- "error: Name or service not known\n");
- check_ai ("t.nxdomain.example", "80", AF_INET6,
- "error: Name or service not known\n");
-
test_bug_21295 ();
+ test_nodata_nxdomain ();
resolv_test_end (aux);
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index 0cf87c224dff5c66..2c4b6d6793a4c3a9 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -242,28 +242,26 @@ convert_hostent_to_gaih_addrtuple (const struct addrinfo *req,
#define gethosts(_family, _type) \
{ \
struct hostent th; \
- struct hostent *h; \
char *localcanon = NULL; \
no_data = 0; \
- while (1) { \
- status = DL_CALL_FCT (fct, (name, _family, &th, \
- tmpbuf->data, tmpbuf->length, \
- &errno, &h_errno, NULL, &localcanon)); \
- if (errno != ERANGE || h_errno != NETDB_INTERNAL) \
- break; \
- if (!scratch_buffer_grow (tmpbuf)) \
- { \
- __resolv_context_enable_inet6 (res_ctx, res_enable_inet6); \
- __resolv_context_put (res_ctx); \
- result = -EAI_MEMORY; \
- goto free_and_return; \
- } \
- } \
- if (status == NSS_STATUS_SUCCESS && errno == 0) \
- h = &th; \
- else \
- h = NULL; \
- if (errno != 0) \
+ while (1) \
+ { \
+ status = DL_CALL_FCT (fct, (name, _family, &th, \
+ tmpbuf->data, tmpbuf->length, \
+ &errno, &h_errno, NULL, &localcanon)); \
+ if (status != NSS_STATUS_TRYAGAIN || h_errno != NETDB_INTERNAL \
+ || errno != ERANGE) \
+ break; \
+ if (!scratch_buffer_grow (tmpbuf)) \
+ { \
+ __resolv_context_enable_inet6 (res_ctx, res_enable_inet6); \
+ __resolv_context_put (res_ctx); \
+ result = -EAI_MEMORY; \
+ goto free_and_return; \
+ } \
+ } \
+ if (status == NSS_STATUS_NOTFOUND \
+ || status == NSS_STATUS_TRYAGAIN || status == NSS_STATUS_UNAVAIL) \
{ \
if (h_errno == NETDB_INTERNAL) \
{ \
@@ -277,9 +275,9 @@ convert_hostent_to_gaih_addrtuple (const struct addrinfo *req,
else \
no_data = h_errno == NO_DATA; \
} \
- else if (h != NULL) \
+ else if (status == NSS_STATUS_SUCCESS) \
{ \
- if (!convert_hostent_to_gaih_addrtuple (req, _family,h, &addrmem)) \
+ if (!convert_hostent_to_gaih_addrtuple (req, _family, &th, &addrmem)) \
{ \
__resolv_context_enable_inet6 (res_ctx, res_enable_inet6); \
__resolv_context_put (res_ctx); \