2 files changed, 51 insertions, 0 deletions
diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index 3709222..64b3575 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -262,6 +262,7 @@ tests := \
   tst-bz11319-fortify2 \
   tst-cookie \
   tst-dprintf-length \
+  tst-fclose-devzero \
   tst-fclose-offset \
   tst-fdopen \
   tst-fdopen2 \
diff --git a/stdio-common/tst-fclose-devzero.c b/stdio-common/tst-fclose-devzero.c
new file mode 100644
index 0000000..1c7b39a
--- /dev/null
+++ b/stdio-common/tst-fclose-devzero.c
@@ -0,0 +1,50 @@
+/* Test that always-zero lseek does not cause fclose failure after fread.
+   Copyright (C) 2025 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 <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <support/check.h>
+#include <support/xstdio.h>
+
+int
+do_test (void)
+{
+  for (int do_ftello = 0; do_ftello < 2; ++do_ftello)
+    {
+      FILE *fp = xfopen ("/dev/zero", "r");
+      char buf[17];
+      memset (buf, 0xcc, sizeof (buf));
+      xfread (buf, 1, sizeof (buf), fp);
+      static const char zeros[sizeof (buf)] = { 0 };
+      TEST_COMPARE_BLOB (buf, sizeof (buf), zeros, sizeof (zeros));
+      if (do_ftello)
+        {
+          errno = 0;
+          TEST_COMPARE (ftello (fp), -1);
+          TEST_COMPARE (errno, ESPIPE);
+        }
+      /* Do not use xfclose because it flushes first.  */
+      TEST_COMPARE (fclose (fp), 0);
+    }
+
+  return 0;
+}
+
+#include <support/test-driver.c>