glibc/glibc-rh1810142-4.patch

97 lines
3.6 KiB
Diff
Raw Normal View History

From: Florian Weimer <fweimer@redhat.com>
Date: Tue, 21 Jan 2020 16:25:39 +0000 (+0100)
Subject: resolv: Enhance __resolv_conf_load to capture file change data
X-Git-Url: https://sourceware.org/git/?p=glibc.git;a=commitdiff_plain;h=dd0b4df329ff7ff2a656404db271c8ee8379ff9d
resolv: Enhance __resolv_conf_load to capture file change data
The data is captured after reading the file. This allows callers
to check the change data against an earlier measurement.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
diff --git a/resolv/res_init.c b/resolv/res_init.c
index 09345718cd..98d84f264d 100644
--- a/resolv/res_init.c
+++ b/resolv/res_init.c
@@ -103,6 +103,7 @@
#include <inet/net-internal.h>
#include <errno.h>
#include <resolv_conf.h>
+#include <file_change_detection.h>
static uint32_t net_mask (struct in_addr);
@@ -549,7 +550,8 @@ res_vinit_1 (FILE *fp, struct resolv_conf_parser *parser)
}
struct resolv_conf *
-__resolv_conf_load (struct __res_state *preinit)
+__resolv_conf_load (struct __res_state *preinit,
+ struct file_change_detection *change)
{
/* Ensure that /etc/hosts.conf has been loaded (once). */
_res_hconf_init ();
@@ -577,7 +579,13 @@ __resolv_conf_load (struct __res_state *preinit)
resolv_conf_parser_init (&parser, preinit);
struct resolv_conf *conf = NULL;
- if (res_vinit_1 (fp, &parser))
+ bool ok = res_vinit_1 (fp, &parser);
+ if (ok && change != NULL)
+ /* Update the file change information if the configuration was
+ loaded successfully. */
+ ok = file_change_detection_for_fp (change, fp);
+
+ if (ok)
{
parser.template.nameserver_list
= nameserver_list_begin (&parser.nameserver_list);
@@ -615,7 +623,7 @@ __res_vinit (res_state statp, int preinit)
if (preinit && has_preinit_values (statp))
/* For the preinit case, we cannot use the cached configuration
because some settings could be different. */
- conf = __resolv_conf_load (statp);
+ conf = __resolv_conf_load (statp, NULL);
else
conf = __resolv_conf_get_current ();
if (conf == NULL)
diff --git a/resolv/resolv_conf.c b/resolv/resolv_conf.c
index d954ba9a5a..bdd2ebb909 100644
--- a/resolv/resolv_conf.c
+++ b/resolv/resolv_conf.c
@@ -136,7 +136,7 @@ __resolv_conf_get_current (void)
{
/* Parse configuration while holding the lock. This avoids
duplicate work. */
- conf = __resolv_conf_load (NULL);
+ conf = __resolv_conf_load (NULL, NULL);
if (conf != NULL)
{
if (global_copy->conf_current != NULL)
diff --git a/resolv/resolv_conf.h b/resolv/resolv_conf.h
index 01cbff9111..101e14bfe5 100644
--- a/resolv/resolv_conf.h
+++ b/resolv/resolv_conf.h
@@ -63,12 +63,16 @@ struct resolv_conf
and the struct resolv_context facility. */
struct __res_state;
+struct file_change_detection;
/* Read /etc/resolv.conf and return a configuration object, or NULL if
/etc/resolv.conf cannot be read due to memory allocation errors.
- If PREINIT is not NULL, some configuration values are taken from the
- struct __res_state object. */
-struct resolv_conf *__resolv_conf_load (struct __res_state *preinit)
+ If PREINIT is not NULL, some configuration values are taken from
+ the struct __res_state object. If CHANGE is not null, file change
+ detection data is written to *CHANGE, based on the state of the
+ file after reading it. */
+struct resolv_conf *__resolv_conf_load (struct __res_state *preinit,
+ struct file_change_detection *change)
attribute_hidden __attribute__ ((warn_unused_result));
/* Return a configuration object for the current /etc/resolv.conf