[PATCH] getdelim: ensure error indicator is set on error (bug 29917)

[Andreas Schwab <schwab@suse.de>]

POSIX requires that getdelim and getline set the error indicator on the
stream when an error occured, in addition to setting errno.
---
 libio/Makefile       |  2 +-
 libio/iogetdelim.c   | 16 +++++++++++-----
 libio/tst-getdelim.c | 36 ++++++++++++++++++++++++++++++++++++
 3 files changed, 48 insertions(+), 6 deletions(-)
 create mode 100644 libio/tst-getdelim.c

diff --git a/libio/Makefile b/libio/Makefile
index 64398ab1ee..9c69a85c87 100644
--- a/libio/Makefile
+++ b/libio/Makefile
@@ -66,7 +66,7 @@ tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc   \
 	tst-fwrite-error tst-ftell-partial-wide tst-ftell-active-handler \
 	tst-ftell-append tst-fputws tst-bz22415 tst-fgetc-after-eof \
 	tst-sprintf-ub tst-sprintf-chk-ub tst-bz24051 tst-bz24153 \
-	tst-wfile-sync tst-bz28828
+	tst-wfile-sync tst-bz28828 tst-getdelim
 
 tests-internal = tst-vtables tst-vtables-interposed
 
diff --git a/libio/iogetdelim.c b/libio/iogetdelim.c
index b6c4c07b45..591526e9c1 100644
--- a/libio/iogetdelim.c
+++ b/libio/iogetdelim.c
@@ -43,11 +43,6 @@ __getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
   ssize_t cur_len = 0;
   ssize_t len;
 
-  if (lineptr == NULL || n == NULL)
-    {
-      __set_errno (EINVAL);
-      return -1;
-    }
   CHECK_FILE (fp, -1);
   _IO_acquire_lock (fp);
   if (_IO_ferror_unlocked (fp))
@@ -56,12 +51,21 @@ __getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
       goto unlock_return;
     }
 
+  if (lineptr == NULL || n == NULL)
+    {
+      __set_errno (EINVAL);
+      fseterr_unlocked (fp);
+      result = -1;
+      goto unlock_return;
+    }
+
   if (*lineptr == NULL || *n == 0)
     {
       *n = 120;
       *lineptr = (char *) malloc (*n);
       if (*lineptr == NULL)
 	{
+	  fseterr_unlocked (fp);
 	  result = -1;
 	  goto unlock_return;
 	}
@@ -88,6 +92,7 @@ __getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
       if (__glibc_unlikely (len >= SSIZE_MAX - cur_len))
 	{
 	  __set_errno (EOVERFLOW);
+	  fseterr_unlocked (fp);
 	  result = -1;
 	  goto unlock_return;
 	}
@@ -102,6 +107,7 @@ __getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
 	  new_lineptr = (char *) realloc (*lineptr, needed);
 	  if (new_lineptr == NULL)
 	    {
+	      fseterr_unlocked (fp);
 	      result = -1;
 	      goto unlock_return;
 	    }
diff --git a/libio/tst-getdelim.c b/libio/tst-getdelim.c
new file mode 100644
index 0000000000..a43674bf20
--- /dev/null
+++ b/libio/tst-getdelim.c
@@ -0,0 +1,36 @@
+/* Check that getdelim sets error indicator on error (BZ #29917)
+
+   Copyright (C) 2022 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 <stdio.h>
+#include <errno.h>
+
+#include <support/check.h>
+
+static int
+do_test (void)
+{
+  clearerr (stdin);
+  TEST_VERIFY (getdelim (0, 0, '\n', stdin) == EOF);
+  TEST_VERIFY (ferror (stdin) != 0);
+  TEST_VERIFY (errno == EINVAL);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
-- 
2.39.0


-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."