@@ -178,6 +178,7 @@ tests := \
tst-endian \
tst-inlcall \
tst-memmove-overflow \
+ tst-strerror-fail \
tst-strfry \
tst-strlcat \
tst-strlcpy \
@@ -43,10 +43,15 @@ __strerror_l (int errnum, locale_t loc)
struct tls_internal_t *tls_internal = __glibc_tls_internal ();
free (tls_internal->strerror_l_buf);
if (__asprintf (&tls_internal->strerror_l_buf, "%s%d",
- translate ("Unknown error ", loc), errnum) == -1)
- tls_internal->strerror_l_buf = NULL;
-
- err = tls_internal->strerror_l_buf;
+ translate ("Unknown error ", loc), errnum) > 0)
+ err = tls_internal->strerror_l_buf;
+ else
+ {
+ /* The pointer was freed above. */
+ tls_internal->strerror_l_buf = NULL;
+ /* Provide a fallback translation. */
+ err = (char *) translate ("Unknown error", loc);
+ }
}
else
err = (char *) translate (err, loc);
new file mode 100644
@@ -0,0 +1,77 @@
+/* Check that strerror, strerror_l do not return NULL on failure (bug 30555).
+ 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 <locale.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/xdlfcn.h>
+
+/* Interposed malloc that can be used to inject allocation failures. */
+
+static volatile bool fail_malloc;
+
+void *
+malloc (size_t size)
+{
+ if (fail_malloc)
+ return NULL;
+
+ static void *(*original_malloc) (size_t);
+ if (original_malloc == NULL)
+ original_malloc = xdlsym (RTLD_NEXT, "malloc");
+ return original_malloc (size);
+}
+
+/* Callbacks for the actual tests. Use fork to run both tests with a
+ clean state. */
+
+static void
+test_strerror (void *closure)
+{
+ fail_malloc = true;
+ const char *s = strerror (999);
+ fail_malloc = false;
+ TEST_COMPARE_STRING (s, "Unknown error");
+}
+
+static void
+test_strerror_l (void *closure)
+{
+ locale_t loc = newlocale (LC_ALL, "C", (locale_t) 0);
+ TEST_VERIFY (loc != (locale_t) 0);
+ fail_malloc = true;
+ const char *s = strerror_l (999, loc);
+ fail_malloc = false;
+ TEST_COMPARE_STRING (s, "Unknown error");
+ freelocale (loc);
+}
+
+static int
+do_test (void)
+{
+ support_isolate_in_subprocess (test_strerror, NULL);
+ support_isolate_in_subprocess (test_strerror_l, NULL);
+
+ return 0;
+}
+
+#include <support/test-driver.c>
For strerror, this fixes commit 28aff047818eb1726394296d27b ("string: Implement strerror in terms of strerror_l"). This commit avoids returning NULL for strerror_l as well, although POSIX allows this behavior for strerror_l. Tested on x86_64-linux-gnu. The test reproduces the bug before the fix. --- string/Makefile | 1 + string/strerror_l.c | 13 +++++--- string/tst-strerror-fail.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 87 insertions(+), 4 deletions(-) base-commit: 388ae538ddcb05c7d8966147b488a5f6e481656e