[LTP] [PATCH v7 1/4] futex_wait06: Add EFAULT error coverage test

[Michael Menasherov]

futex(FUTEX_WAIT) has no existing test for EFAULT. Add coverage for
the cases where uaddr points to unmapped memory and where the timeout
pointer is invalid.

Signed-off-by: Michael Menasherov <mmenashe@redhat.com>
---
 runtest/syscalls                              |  1 +
 testcases/kernel/syscalls/futex/.gitignore    |  1 +
 .../kernel/syscalls/futex/futex_wait06.c      | 75 +++++++++++++++++++
 3 files changed, 77 insertions(+)
 create mode 100644 testcases/kernel/syscalls/futex/futex_wait06.c

diff --git a/runtest/syscalls b/runtest/syscalls
index f790e8f84..e8ef890f3 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -1907,3 +1907,4 @@ io_uring03 io_uring03
 
 # Tests below may cause kernel memory leak
 perf_event_open03 perf_event_open03
+futex_wait06 futex_wait06
diff --git a/testcases/kernel/syscalls/futex/.gitignore b/testcases/kernel/syscalls/futex/.gitignore
index 9d08ba7d3..56596dcb4 100644
--- a/testcases/kernel/syscalls/futex/.gitignore
+++ b/testcases/kernel/syscalls/futex/.gitignore
@@ -13,3 +13,4 @@
 /futex_waitv01
 /futex_waitv02
 /futex_waitv03
+/futex_wait06
diff --git a/testcases/kernel/syscalls/futex/futex_wait06.c b/testcases/kernel/syscalls/futex/futex_wait06.c
new file mode 100644
index 000000000..2cf509ee1
--- /dev/null
+++ b/testcases/kernel/syscalls/futex/futex_wait06.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Red Hat, Inc. Michael Menasherov <mmenashe@redhat.com>
+ */
+
+/*\
+ * Check that futex(FUTEX_WAIT) returns EFAULT when:
+ *
+ * 1) uaddr points to unmapped memory
+ * 2) timeout points to unmapped memory
+ */
+#include <errno.h>
+#include <sys/mman.h>
+
+#include "futextest.h"
+
+static futex_t futex = FUTEX_INITIALIZER;
+static futex_t *bad;
+
+static struct futex_test_variants variants[] = {
+#if (__NR_futex != __LTP__NR_INVALID_SYSCALL)
+	{ .fntype = FUTEX_FN_FUTEX, .tstype = TST_KERN_OLD_TIMESPEC, .desc = "syscall with old kernel spec"},
+#endif
+
+#if (__NR_futex_time64 != __LTP__NR_INVALID_SYSCALL)
+	{ .fntype = FUTEX_FN_FUTEX64, .tstype = TST_KERN_TIMESPEC, .desc = "syscall time64 with kernel spec"},
+#endif
+};
+
+static struct testcase {
+	const char *desc;
+	futex_t **uaddr;
+	void **timeout;
+} testcases[] = {
+	{
+		.desc = "uaddr points to unmapped memory",
+		.uaddr = &bad,
+		.timeout = NULL,
+	},
+	{
+		.desc = "timeout points to unmapped memory",
+		.uaddr = NULL,
+		.timeout = (void **)&bad,
+	},
+};
+
+static void run(unsigned int n)
+{
+	struct futex_test_variants *tv = &variants[tst_variant];
+	struct testcase *tc = &testcases[n];
+	futex_t *uaddr = tc->uaddr ? *tc->uaddr : &futex;
+	void *timeout = tc->timeout ? *tc->timeout : NULL;
+
+	TST_EXP_FAIL(futex_syscall(tv->fntype, uaddr, FUTEX_WAIT, futex,
+		timeout, NULL, 0, 0), EFAULT, "%s", tc->desc);
+}
+
+static void setup(void)
+{
+	struct futex_test_variants *tv = &variants[tst_variant];
+
+	tst_res(TINFO, "Testing variant: %s", tv->desc);
+	futex_supported_by_kernel(tv->fntype);
+
+	bad = SAFE_MMAP(NULL, getpagesize(), PROT_READ | PROT_WRITE,
+		MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	SAFE_MUNMAP((void *)bad, getpagesize());
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.test = run,
+	.tcnt = ARRAY_SIZE(testcases),
+	.test_variants = ARRAY_SIZE(variants),
+};
-- 
2.54.0