From: André Almeida <andrealmeid@igalia.com>

Commit d8e2f919997 ("selftests/futex: Fix some futex_numa_mpol
subtests") removed the "Memory out of range" subtest due to it being
dependent on the memory layout of the test process having an invalid
memory address just after the `*futex_ptr` allocated memory.

Reintroduce this test and make it deterministic, by allocation two
memory pages and marking the second one with PROT_NONE.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 .../testing/selftests/futex/functional/futex_numa_mpol.c  | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/futex/functional/futex_numa_mpol.c b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
index dd7b05e8cda45..5f4e3111269c3 100644
--- a/tools/testing/selftests/futex/functional/futex_numa_mpol.c
+++ b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
@@ -174,10 +174,13 @@ int main(int argc, char *argv[])
 	ksft_set_plan(1);
 
 	mem_size = sysconf(_SC_PAGE_SIZE);
-	futex_ptr = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+	futex_ptr = mmap(NULL, mem_size * 2, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
 	if (futex_ptr == MAP_FAILED)
 		ksft_exit_fail_msg("mmap() for %d bytes failed\n", mem_size);
 
+	/* Create an invalid memory region for the "Memory out of range" test */
+	mprotect(futex_ptr + mem_size, mem_size, PROT_NONE);
+
 	futex_numa = futex_ptr;
 
 	ksft_print_msg("Regular test\n");
@@ -192,6 +195,9 @@ int main(int argc, char *argv[])
 	ksft_print_msg("Mis-aligned futex\n");
 	test_futex(futex_ptr + mem_size - 4, EINVAL);
 
+	ksft_print_msg("Memory out of range\n");
+	test_futex(futex_ptr + mem_size, EFAULT);
+
 	futex_numa->numa = FUTEX_NO_NODE;
 	mprotect(futex_ptr, mem_size, PROT_READ);
 	ksft_print_msg("Memory, RO\n");
-- 
2.51.0

The following commit has been merged into the locking/futex branch of tip:

Commit-ID:     2951dddef0a87c20e83c77070bd5077290d9121f
Gitweb:        https://git.kernel.org/tip/2951dddef0a87c20e83c77070bd5077290d9121f
Author:        André Almeida <andrealmeid@igalia.com>
AuthorDate:    Mon, 15 Sep 2025 23:26:29 +02:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 17 Sep 2025 19:48:44 +02:00

selftest/futex: Reintroduce "Memory out of range" numa_mpol's subtest

Commit d8e2f919997 ("selftests/futex: Fix some futex_numa_mpol
subtests") removed the "Memory out of range" subtest due to it being
dependent on the memory layout of the test process having an invalid
memory address just after the `*futex_ptr` allocated memory.

Reintroduce this test and make it deterministic, by allocation two
memory pages and marking the second one with PROT_NONE.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Waiman Long <longman@redhat.com>
---
 tools/testing/selftests/futex/functional/futex_numa_mpol.c | 8 ++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/futex/functional/futex_numa_mpol.c b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
index dd7b05e..5f4e311 100644
--- a/tools/testing/selftests/futex/functional/futex_numa_mpol.c
+++ b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
@@ -174,10 +174,13 @@ int main(int argc, char *argv[])
 	ksft_set_plan(1);
 
 	mem_size = sysconf(_SC_PAGE_SIZE);
-	futex_ptr = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+	futex_ptr = mmap(NULL, mem_size * 2, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
 	if (futex_ptr == MAP_FAILED)
 		ksft_exit_fail_msg("mmap() for %d bytes failed\n", mem_size);
 
+	/* Create an invalid memory region for the "Memory out of range" test */
+	mprotect(futex_ptr + mem_size, mem_size, PROT_NONE);
+
 	futex_numa = futex_ptr;
 
 	ksft_print_msg("Regular test\n");
@@ -192,6 +195,9 @@ int main(int argc, char *argv[])
 	ksft_print_msg("Mis-aligned futex\n");
 	test_futex(futex_ptr + mem_size - 4, EINVAL);
 
+	ksft_print_msg("Memory out of range\n");
+	test_futex(futex_ptr + mem_size, EFAULT);
+
 	futex_numa->numa = FUTEX_NO_NODE;
 	mprotect(futex_ptr, mem_size, PROT_READ);
 	ksft_print_msg("Memory, RO\n");