From 299210c1fa67e2dfb564475986fce11cd33db9ad Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 16 Jul 2020 16:12:46 +0200
Subject: [PATCH 01/11] nss_files: Consolidate file opening in
__nss_files_fopen
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
---
include/nss_files.h | 28 ++++++++++++++++++++++++
nss/Makefile | 2 +-
nss/Versions | 1 +
nss/nss_files/files-XXX.c | 3 ++-
nss/nss_files/files-alias.c | 5 +++--
nss/nss_files/files-initgroups.c | 6 ++---
nss/nss_files/files-netgrp.c | 5 ++---
nss/nss_files_fopen.c | 47 ++++++++++++++++++++++++++++++++++++++++
8 files changed, 86 insertions(+), 11 deletions(-)
create mode 100644 include/nss_files.h
create mode 100644 nss/nss_files_fopen.c
diff -rupN a/include/nss_files.h b/include/nss_files.h
--- a/include/nss_files.h 1969-12-31 19:00:00.000000000 -0500
+++ b/include/nss_files.h 2020-09-11 21:28:42.027034988 -0400
@@ -0,0 +1,28 @@
+/* Internal routines for nss_files.
+ Copyright (C) 2020 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
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _NSS_FILES_H
+#define _NSS_FILES_H
+
+#include <stdio.h>
+
+/* Open PATH for reading, as a data source for nss_files. */
+FILE *__nss_files_fopen (const char *path);
+libc_hidden_proto (__nss_files_fopen)
+
+#endif /* _NSS_FILES_H */
diff -rupN a/nss/Makefile b/nss/Makefile
--- a/nss/Makefile 2020-09-11 21:24:05.569544894 -0400
+++ b/nss/Makefile 2020-09-11 21:28:42.035035292 -0400
@@ -28,7 +28,7 @@ headers := nss.h
routines = nsswitch getnssent getnssent_r digits_dots \
valid_field valid_list_field rewrite_field \
$(addsuffix -lookup,$(databases)) \
- compat-lookup nss_hash
+ compat-lookup nss_hash nss_files_fopen
# These are the databases that go through nss dispatch.
# Caution: if you add a database here, you must add its real name
diff -rupN a/nss/Versions b/nss/Versions
--- a/nss/Versions 2020-09-11 21:24:04.852517683 -0400
+++ b/nss/Versions 2020-09-11 21:28:42.041035519 -0400
@@ -21,6 +21,7 @@ libc {
__nss_passwd_lookup2; __nss_group_lookup2; __nss_hosts_lookup2;
__nss_services_lookup2; __nss_next2; __nss_lookup;
__nss_hash; __nss_database_lookup2;
+ __nss_files_fopen;
}
}
diff -rupN a/nss/nss_files/files-XXX.c b/nss/nss_files/files-XXX.c
--- a/nss/nss_files/files-XXX.c 2018-08-01 01:10:47.000000000 -0400
+++ b/nss/nss_files/files-XXX.c 2020-09-11 21:28:42.049035823 -0400
@@ -22,6 +22,7 @@
#include <fcntl.h>
#include <libc-lock.h>
#include "nsswitch.h"
+#include <nss_files.h>
#include <kernel-features.h>
@@ -74,7 +75,7 @@ internal_setent (FILE **stream)
if (*stream == NULL)
{
- *stream = fopen (DATAFILE, "rce");
+ *stream = __nss_files_fopen (DATAFILE);
if (*stream == NULL)
status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
diff -rupN a/nss/nss_files/files-alias.c b/nss/nss_files/files-alias.c
--- a/nss/nss_files/files-alias.c 2020-09-11 21:24:02.004409596 -0400
+++ b/nss/nss_files/files-alias.c 2020-09-11 21:28:42.055036051 -0400
@@ -29,6 +29,7 @@
#include <kernel-features.h>
#include "nsswitch.h"
+#include <nss_files.h>
/* Locks the static variables in this file. */
__libc_lock_define_initialized (static, lock)
@@ -47,7 +48,7 @@ internal_setent (FILE **stream)
if (*stream == NULL)
{
- *stream = fopen ("/etc/aliases", "rce");
+ *stream = __nss_files_fopen ("/etc/aliases");
if (*stream == NULL)
status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
@@ -213,7 +214,7 @@ get_next_alias (FILE *stream, const char
first_unused = cp;
- listfile = fopen (&cp[9], "rce");
+ listfile = __nss_files_fopen (&cp[9]);
/* If the file does not exist we simply ignore
the statement. */
if (listfile != NULL
diff -rupN a/nss/nss_files/files-initgroups.c b/nss/nss_files/files-initgroups.c
--- a/nss/nss_files/files-initgroups.c 2018-08-01 01:10:47.000000000 -0400
+++ b/nss/nss_files/files-initgroups.c 2020-09-11 22:08:25.130740010 -0400
@@ -25,22 +25,20 @@
#include <stdbool.h>
#include <stdlib.h>
#include <scratch_buffer.h>
+#include <nss_files.h>
enum nss_status
_nss_files_initgroups_dyn (const char *user, gid_t group, long int *start,
long int *size, gid_t **groupsp, long int limit,
int *errnop)
{
- FILE *stream = fopen ("/etc/group", "rce");
+ FILE *stream = __nss_files_fopen ("/etc/group");
if (stream == NULL)
{
*errnop = errno;
return *errnop == ENOMEM ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
}
- /* No other thread using this stream. */
- __fsetlocking (stream, FSETLOCKING_BYCALLER);
-
char *line = NULL;
size_t linelen = 0;
enum nss_status status = NSS_STATUS_SUCCESS;
diff -rupN a/nss/nss_files/files-netgrp.c b/nss/nss_files/files-netgrp.c
--- a/nss/nss_files/files-netgrp.c 2018-08-01 01:10:47.000000000 -0400
+++ b/nss/nss_files/files-netgrp.c 2020-09-11 21:28:42.068036544 -0400
@@ -26,6 +26,7 @@
#include <string.h>
#include "nsswitch.h"
#include "netgroup.h"
+#include <nss_files.h>
#define DATAFILE "/etc/netgroup"
@@ -62,7 +63,7 @@ _nss_files_setnetgrent (const char *grou
return NSS_STATUS_UNAVAIL;
/* Find the netgroups file and open it. */
- fp = fopen (DATAFILE, "rce");
+ fp = __nss_files_fopen (DATAFILE);
if (fp == NULL)
status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
else
@@ -76,8 +77,6 @@ _nss_files_setnetgrent (const char *grou
status = NSS_STATUS_NOTFOUND;
result->cursor = result->data;
- __fsetlocking (fp, FSETLOCKING_BYCALLER);
-
while (!feof_unlocked (fp))
{
ssize_t curlen = getline (&line, &line_len, fp);
diff -rupN a/nss/nss_files_fopen.c b/nss/nss_files_fopen.c
--- a/nss/nss_files_fopen.c 1969-12-31 19:00:00.000000000 -0500
+++ b/nss/nss_files_fopen.c 2020-09-11 21:28:42.074036771 -0400
@@ -0,0 +1,47 @@
+/* Open an nss_files database file.
+ Copyright (C) 2020 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <nss_files.h>
+
+#include <errno.h>
+#include <stdio_ext.h>
+
+FILE *
+__nss_files_fopen (const char *path)
+{
+ FILE *fp = fopen (path, "rce");
+ if (fp == NULL)
+ return NULL;
+
+ /* The stream is not shared across threads. */
+ __fsetlocking (fp, FSETLOCKING_BYCALLER);
+
+ /* This tells libio that the file is seekable, and that fp->_offset
+ is correct, ensuring that __ftello64 is efficient (bug 26257). */
+ if (__fseeko64 (fp, 0, SEEK_SET) < 0)
+ {
+ /* nss_files requires seekable files, to deal with repeated
+ reads of the same line after reporting ERANGE. */
+ fclose (fp);
+ __set_errno (ESPIPE);
+ return NULL;
+ }
+
+ return fp;
+}
+libc_hidden_def (__nss_files_fopen)