From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Subject: [PATCH] gshadow: Matching sgetsgent, sgetsgent_r ERANGE handling (bug 30151)
Date: Tue, 21 Feb 2023 09:39:30 +0100 [thread overview]
Message-ID: <875ybvs98d.fsf@oldenburg.str.redhat.com> (raw)
Before this change, sgetsgent_r did not set errno to ERNAGE, but
sgetsgent only checked errno, not the return value from sgetsgent_r.
Consequently, sgetsgent did not detect any error, and reported
success to the caller, without initializing the struct sgrp object
whose address was returned.
This commit changes sgetsgent_r to set errno as well. This avoids
similar issues in applications which only change errno.
Tested on x86_64-linux-gnu.
---
gshadow/Makefile | 2 +-
gshadow/sgetsgent_r.c | 5 +++-
gshadow/tst-sgetsgent.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 74 insertions(+), 2 deletions(-)
diff --git a/gshadow/Makefile b/gshadow/Makefile
index 796fbbf473..a95524593a 100644
--- a/gshadow/Makefile
+++ b/gshadow/Makefile
@@ -26,7 +26,7 @@ headers = gshadow.h
routines = getsgent getsgnam sgetsgent fgetsgent putsgent \
getsgent_r getsgnam_r sgetsgent_r fgetsgent_r
-tests = tst-gshadow tst-putsgent tst-fgetsgent_r
+tests = tst-gshadow tst-putsgent tst-fgetsgent_r tst-sgetsgent
CFLAGS-getsgent_r.c += -fexceptions
CFLAGS-getsgent.c += -fexceptions
diff --git a/gshadow/sgetsgent_r.c b/gshadow/sgetsgent_r.c
index ea085e91d7..c75624e1f7 100644
--- a/gshadow/sgetsgent_r.c
+++ b/gshadow/sgetsgent_r.c
@@ -61,7 +61,10 @@ __sgetsgent_r (const char *string, struct sgrp *resbuf, char *buffer,
buffer[buflen - 1] = '\0';
sp = strncpy (buffer, string, buflen);
if (buffer[buflen - 1] != '\0')
- return ERANGE;
+ {
+ __set_errno (ERANGE);
+ return ERANGE;
+ }
}
else
sp = (char *) string;
diff --git a/gshadow/tst-sgetsgent.c b/gshadow/tst-sgetsgent.c
new file mode 100644
index 0000000000..0370c10fd0
--- /dev/null
+++ b/gshadow/tst-sgetsgent.c
@@ -0,0 +1,69 @@
+/* Test large input for sgetsgent (bug 30151).
+ Copyright (C) 2023 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 <gshadow.h>
+#include <stddef.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xmemstream.h>
+#include <stdlib.h>
+
+static int
+do_test (void)
+{
+ /* Create a shadow group with 1000 members. */
+ struct xmemstream mem;
+ xopen_memstream (&mem);
+ const char *passwd = "k+zD0nucwfxAo3sw1NXUj6K5vt5M16+X0TVGdE1uFvq5R8V7efJ";
+ fprintf (mem.out, "group-name:%s::m0", passwd);
+ for (int i = 1; i < 1000; ++i)
+ fprintf (mem.out, ",m%d", i);
+ xfclose_memstream (&mem);
+
+ /* Call sgetsgent. */
+ char *input = mem.buffer;
+ struct sgrp *e = sgetsgent (input);
+ TEST_VERIFY_EXIT (e != NULL);
+ TEST_COMPARE_STRING (e->sg_namp, "group-name");
+ TEST_COMPARE_STRING (e->sg_passwd, passwd);
+ /* No administrators. */
+ TEST_COMPARE_STRING (e->sg_adm[0], NULL);
+ /* Check the members list. */
+ for (int i = 0; i < 1000; ++i)
+ {
+ char *member = xasprintf ("m%d", i);
+ TEST_COMPARE_STRING (e->sg_mem[i], member);
+ free (member);
+ }
+ TEST_COMPARE_STRING (e->sg_mem[1000], NULL);
+
+ /* Check that putsgent brings back the input string. */
+ xopen_memstream (&mem);
+ TEST_COMPARE (putsgent (e, mem.out), 0);
+ xfclose_memstream (&mem);
+ /* Compare without the trailing '\n' that putsgent added. */
+ TEST_COMPARE (mem.buffer[mem.length - 1], '\n');
+ mem.buffer[mem.length - 1] = '\0';
+ TEST_COMPARE_STRING (mem.buffer, input);
+
+ free (mem.buffer);
+ free (input);
+ return 0;
+}
+
+#include <support/test-driver.c>
base-commit: 8b014a1b1f7aee1e3348db108aeea396359d481e
next reply other threads:[~2023-02-21 8:39 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-21 8:39 Florian Weimer [this message]
2023-02-21 9:21 ` Sam James
2023-02-21 9:45 ` Florian Weimer
2023-03-01 18:20 ` Siddhesh Poyarekar
2023-03-07 9:06 ` Florian Weimer
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