Add selftests for the bpf_cpumask_fill helper that sets a bpf_cpumask to
a bit pattern provided by a BPF program.
Signed-off-by: Emil Tsalapatis (Meta) <emil@xxxxxxxxxxxxxxx>
---
.../selftests/bpf/prog_tests/verifier.c | 2 +
.../selftests/bpf/progs/cpumask_success.c | 23 ++++++
.../selftests/bpf/progs/verifier_cpumask.c | 77 +++++++++++++++++++
3 files changed, 102 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/verifier_cpumask.c
diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index 8a0e1ff8a2dc..4dd95e93bd7e 100644
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -23,6 +23,7 @@
#include "verifier_cgroup_storage.skel.h"
#include "verifier_const.skel.h"
#include "verifier_const_or.skel.h"
+#include "verifier_cpumask.skel.h"
#include "verifier_ctx.skel.h"
#include "verifier_ctx_sk_msg.skel.h"
#include "verifier_d_path.skel.h"
@@ -155,6 +156,7 @@ void test_verifier_cgroup_skb(void) { RUN(verifier_cgroup_skb); }
void test_verifier_cgroup_storage(void) { RUN(verifier_cgroup_storage); }
void test_verifier_const(void) { RUN(verifier_const); }
void test_verifier_const_or(void) { RUN(verifier_const_or); }
+void test_verifier_cpumask(void) { RUN(verifier_cpumask); }
void test_verifier_ctx(void) { RUN(verifier_ctx); }
void test_verifier_ctx_sk_msg(void) { RUN(verifier_ctx_sk_msg); }
void test_verifier_d_path(void) { RUN(verifier_d_path); }
diff --git a/tools/testing/selftests/bpf/progs/cpumask_success.c b/tools/testing/selftests/bpf/progs/cpumask_success.c
index 80ee469b0b60..f252aa2f3090 100644
--- a/tools/testing/selftests/bpf/progs/cpumask_success.c
+++ b/tools/testing/selftests/bpf/progs/cpumask_success.c
@@ -770,3 +770,26 @@ int BPF_PROG(test_refcount_null_tracking, struct task_struct *task, u64 clone_fl
bpf_cpumask_release(mask2);
return 0;
}
+
+SEC("syscall")
+__success
+int BPF_PROG(test_fill_reject_small_mask)
+{
+ struct bpf_cpumask *local;
+ u8 toofewbits;
+ int ret;
+
+ local = create_cpumask();
+ if (!local)
+ return 0;
+
+ /* The kfunc should prevent this operation */
+ ret = bpf_cpumask_fill((struct cpumask *)local, &toofewbits, sizeof(toofewbits));
+ if (ret != -EACCES)
+ err = 2;
+
+ bpf_cpumask_release(local);
+
+ return 0;
+}
+
diff --git a/tools/testing/selftests/bpf/progs/verifier_cpumask.c b/tools/testing/selftests/bpf/progs/verifier_cpumask.c
new file mode 100644
index 000000000000..bb84dd36beac
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_cpumask.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
+
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+#include "cpumask_common.h"
+
+#define CPUMASK_TEST_MASKLEN (8 * sizeof(u64))
+
+u64 bits[CPUMASK_TEST_MASKLEN];
+
+SEC("syscall")
+__success
+int BPF_PROG(test_cpumask_fill)
+{
+ struct bpf_cpumask *mask;
+ int ret;
+
+ mask = bpf_cpumask_create();
+ if (!mask) {
+ err = 1;
+ return 0;
+ }
+
+ ret = bpf_cpumask_fill((struct cpumask *)mask, bits, CPUMASK_TEST_MASKLEN);
+ if (!ret)
+ err = 2;
+
+ if (mask)
+ bpf_cpumask_release(mask);
+
+ return 0;
+}
+
+SEC("syscall")
+__description("bpf_cpumask_fill: invalid cpumask target")
+__failure __msg("type=scalar expected=fp")
+int BPF_PROG(test_cpumask_fill_cpumask_invalid)
+{
+ struct bpf_cpumask *invalid = (struct bpf_cpumask *)0x123456;
+ int ret;
+
+ ret = bpf_cpumask_fill((struct cpumask *)invalid, bits, CPUMASK_TEST_MASKLEN);
+ if (!ret)
+ err = 2;
+
+ return 0;
+}
+
+SEC("syscall")
+__description("bpf_cpumask_fill: invalid cpumask source")
+__failure __msg("leads to invalid memory access")
+int BPF_PROG(test_cpumask_fill_bpf_invalid)
+{
+ void *garbage = (void *)0x123456;
+ struct bpf_cpumask *local;
+ int ret;
+
+ local = create_cpumask();
+ if (!local) {
+ err = 1;
+ return 0;
+ }
+
+ ret = bpf_cpumask_fill((struct cpumask *)local, garbage, CPUMASK_TEST_MASKLEN);
+ if (!ret)
+ err = 2;
+
+ bpf_cpumask_release(local);
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.47.1
